diff --git a/extensions/fablabchemnitz/contour_scanner_and_trimmer/contour_scanner_and_trimmer.inx b/extensions/fablabchemnitz/contour_scanner_and_trimmer/contour_scanner_and_trimmer.inx
index 8ccb52a1..7e3f2f05 100644
--- a/extensions/fablabchemnitz/contour_scanner_and_trimmer/contour_scanner_and_trimmer.inx
+++ b/extensions/fablabchemnitz/contour_scanner_and_trimmer/contour_scanner_and_trimmer.inx
@@ -8,11 +8,6 @@
             <param name="show_debug" type="bool" gui-text="Show debug infos">false</param>
             <param name="break_apart" type="bool" gui-text="Break apart input" gui-description="Break apart input paths into sub paths. Modifies original paths: converts to absolute paths and might create additional new path elements.">false</param>   
             <param name="handle_groups" type="bool" gui-text="Handle groups" gui-description="Also looks for paths in groups which are in the current selection. Note: The generated results have a different structure (less granularity due to grouping) than directly selected paths. The colorization for non-intersected paths will be different too.">false</param> 
-            <param name="path_types" type="optiongroup" appearance="combo" gui-text="Scanning selection" gui-description="Process open paths by other open paths, closed paths by other closed paths, or all paths by all other paths">
-                <option value="both">all:all paths</option>
-                <option value="open_paths">open:open paths</option>
-                <option value="closed_paths">closed:closed paths</option>
-            </param>
             <param name="flattenbezier" type="bool" gui-text="Quantization (flatten bezier curves to polylines)" gui-description="Convert bezier curves to polylines.">true</param>  
             <param name="flatness" type="float" min="0.001" max="99999.000" precision="3" gui-text="Flatness (tolerance)" gui-description="Minimum flatness = 0.001. The smaller the value the more fine segments you will get (quantization). Large values might destroy the line continuity.">0.100</param>
             <param name="decimals" type="int" min="0" max="16" gui-text="Decimals" gui-description="Accuracy for sub split lines / lines trimmed by shapely (default: 3)">3</param>
@@ -30,7 +25,7 @@
                     <param name="remove_beziers" type="bool" gui-text="beziers">false</param>     
                     <param name="remove_opened" type="bool" gui-text="opened">false</param>
                     <param name="remove_closed" type="bool" gui-text="closed">false</param>
-                    <param name="remove_self_intersecting" type="bool" gui-text="Remove original self-intersecting paths">false</param>
+                    <param name="remove_self_intersecting" type="bool" gui-text="self-intersecting">false</param>
                 <separator/>
                     <label appearance="header">Highlighting</label>
                     <param name="highlight_relative" type="bool" gui-text="relative cmd paths">false</param>
@@ -47,6 +42,11 @@
                 <separator/>
                 <vbox>
                     <label appearance="header">Trimming</label>
+                <param name="trimming_path_types" type="optiongroup" appearance="combo" gui-text="Trimming selection" gui-description="Process open paths by other open paths, closed paths by other closed paths, or all paths by all other paths. This selection does not apply for paths which intersect themselves!">
+                    <option value="both">all:all paths</option>
+                    <option value="open_paths">open:open paths</option>
+                    <option value="closed_paths">closed:closed paths</option>
+                </param>
                     <param name="draw_trimmed" type="bool" gui-text="Draw trimmed lines">false</param> 
                     <param name="combine_nonintersects" type="bool" gui-text="Chain + combine non-intersected lines">true</param> 
                     <param name="remove_duplicates" type="bool" gui-text="Remove duplicate trim lines">true</param>
@@ -73,8 +73,8 @@
                     <param name="color_bezier" type="color" appearance="colorbutton" gui-text="bezier paths">258744063</param>
                     <param name="color_opened" type="color" appearance="colorbutton" gui-text="opened paths">4012452351</param>
                     <param name="color_closed" type="color" appearance="colorbutton" gui-text="closed paths">2330080511</param>
-                    <param name="color_self_intersecting_paths" type="color" appearance="colorbutton" gui-text="self-intersecting contours">2593756927</param>
-                    <param name="color_self_intersections" type="color" appearance="colorbutton" gui-text="self-intersecting line points">6320383</param>
+                    <param name="color_self_intersecting_paths" type="color" appearance="colorbutton" gui-text="self-intersecting paths">2593756927</param>
+                    <param name="color_self_intersections" type="color" appearance="colorbutton" gui-text="self-intersecting paths points">6320383</param>
                     <param name="color_global_intersections" type="color" appearance="colorbutton" gui-text="global intersection points">4239343359</param>
                 </vbox>
                 <separator/>
@@ -87,8 +87,8 @@
             </hbox>
         </page>
         <page name="tab_tips" gui-text="Tips">
-            <label xml:space="preserve">- Helps to find duplicate lines and to visualize intersections
- - Works for self-intersecting lines too
+            <label xml:space="preserve"> - Helps to find duplicate lines and to visualize intersections
+ - Works for self-intersecting paths too
  - Uses Bentley-Ottmann algorithm to detect intersections
  - Allows to separate different contour types by colors
  - Works with paths which have Live Path Effects (LPE)
@@ -98,7 +98,7 @@ Tips:
  - If nothings is selected, the whole document will be processed, regardless of groups. In contrast, if you made a custom selection, check to handle or not to handle groups.
  - Convert your strokes and objects to paths before
  - Does not work for clones. You will need to unlink them before
- - Use extensions to filter short/unrequired lines
+ - Use extensions to filter short/unrequired paths
  - Use extensions to purge or repair invalid paths
  - Use 'Path > Simplify' or hit 'CTRL + L' to simplify the trimmed result. With a fine quantization setting the simplified paths will be nearly identical to the original path (except the position of control points)</label>
             <label appearance="header">Do not select too much paths at once if you have got a fine settings for quantization. This extension is slow and might calculate hours on ultra high configurations.</label>
diff --git a/extensions/fablabchemnitz/contour_scanner_and_trimmer/contour_scanner_and_trimmer.py b/extensions/fablabchemnitz/contour_scanner_and_trimmer/contour_scanner_and_trimmer.py
index aee3b1f2..a812d8ea 100644
--- a/extensions/fablabchemnitz/contour_scanner_and_trimmer/contour_scanner_and_trimmer.py
+++ b/extensions/fablabchemnitz/contour_scanner_and_trimmer/contour_scanner_and_trimmer.py
@@ -11,7 +11,6 @@ Extension for InkScape 1.0+
           in particular when one line contains another or when two lines are equals.
         - crosses() returns True if the dimension of the intersection is less than the dimension of the one or the other.
           So if two lines overlap, they won't be considered as "crossing". intersection() will return a geometric object.
-
     - replace trimmed paths by bezier paths (calculating lengths and required t parameter)
     - find more duplicates
         - overlapping lines in sub splits
@@ -19,6 +18,7 @@ Extension for InkScape 1.0+
         - duplicates in original selection
         - duplicates in split bezier
         - ...
+    - refactor subSplitData stuff by some clean mapping/structure instead having a lot of useless arays
     
 - important to notice
     - this algorithm might be really slow. Reduce flattening quality to speed up
@@ -227,9 +227,15 @@ class ContourScannerAndTrimmer(inkex.EffectExtension):
 
 
     def buildTrimLineGroups(self, allSubSplitData, subSplitIndex, globalIntersectionPoints, 
-            trimLineIndex, snap_tolerance, apply_original_style): 
+            snap_tolerance, apply_original_style): 
         ''' make a group containing trimmed lines'''      
         
+        #Check if we should skip or process the path anyway   
+        isClosed = allSubSplitData[5][subSplitIndex]
+        if self.options.trimming_path_types == 'open_paths' and isClosed is True: return #skip this call
+        elif self.options.trimming_path_types == 'closed_paths' and isClosed is False: return #skip this call
+        elif self.options.trimming_path_types == 'both': pass
+        
         trimLineStyle = {'stroke': str(self.options.color_trimmed), 'fill': 'none', 'stroke-width': self.options.strokewidth}
            
         linesWithSnappedIntersectionPoints = snap(LineString(allSubSplitData[0][subSplitIndex]), globalIntersectionPoints, snap_tolerance)
@@ -251,7 +257,7 @@ class ContourScannerAndTrimmer(inkex.EffectExtension):
         splitAt = [] #if the sub split line was split by an intersecting line we receive two trim lines with same assigned original path id!
         prevLine = None
         for j in range(len(trimLines)):
-            trimLineId = trimGroupId + "-" + str(trimLineIndex)
+            trimLineId = trimGroupId + "-" + str(subSplitIndex)
             splitAt.append(trimGroupId)
             if splitAt.count(trimGroupId) > 1: #we detected a lines with intersection on
                 trimLineId = trimLineId + self.svg.get_unique_id(intersectedVerb)
@@ -260,7 +266,7 @@ class ContourScannerAndTrimmer(inkex.EffectExtension):
                 (left side and right side of cut) - note: updating element 
                 id sometimes seems not to work if the id was used before in Inkscape
                 '''
-                prevLine.attrib['id'] = trimGroupId + "-" + str(trimLineIndex) + self.svg.get_unique_id(intersectedVerb)
+                prevLine.attrib['id'] = trimGroupId + "-" + str(subSplitIndex) + self.svg.get_unique_id(intersectedVerb)
                 prevLine.attrib['intersected'] = 'True' #some dirty flag we need
             prevLine = trimLine = inkex.PathElement(id=trimLineId)
             #if so.show_debug is True:
@@ -398,36 +404,36 @@ class ContourScannerAndTrimmer(inkex.EffectExtension):
         pars.add_argument("--show_debug", type=inkex.Boolean, default=False, help="Show debug infos")
         pars.add_argument("--break_apart", type=inkex.Boolean, default=False, help="Break apart input paths into sub paths")
         pars.add_argument("--handle_groups", type=inkex.Boolean, default=False, help="Also looks for paths in groups which are in the current selection")
-        pars.add_argument("--path_types", default="closed_paths", help="Process open paths by other open paths, closed paths by other closed paths, or all paths by all other paths")
+        pars.add_argument("--trimming_path_types", default="closed_paths", help="Process open paths by other open paths, closed paths by other closed paths, or all paths by all other paths")
         pars.add_argument("--flattenbezier", type=inkex.Boolean, default=True, help="Flatten bezier curves to polylines")
         pars.add_argument("--flatness", type=float, default=0.1, help="Minimum flatness = 0.001. The smaller the value the more fine segments you will get (quantization). Large values might destroy the line continuity.")
         pars.add_argument("--decimals", type=int, default=3, help="Accuracy for sub split lines / lines trimmed by shapely")
         pars.add_argument("--snap_tolerance", type=float, default=0.1, help="Snap tolerance for intersection points")
 
-       #Scanning - Removing
-        pars.add_argument("--remove_relative", type=inkex.Boolean, default=False, help="Remove original relative cmd paths")
-        pars.add_argument("--remove_absolute", type=inkex.Boolean, default=False, help="Remove original absolute cmd paths")
-        pars.add_argument("--remove_mixed", type=inkex.Boolean, default=False, help="Remove original mixed cmd (relative + absolute) paths")
-        pars.add_argument("--remove_polylines", type=inkex.Boolean, default=False, help="Remove original polyline paths")
-        pars.add_argument("--remove_beziers", type=inkex.Boolean, default=False, help="Remove original bezier paths")
-        pars.add_argument("--remove_opened", type=inkex.Boolean, default=False, help="Remove original opened paths")
-        pars.add_argument("--remove_closed", type=inkex.Boolean, default=False, help="Remove original closed paths")
-        pars.add_argument("--remove_self_intersecting", type=inkex.Boolean, default=False, help="Remove original self-intersecting paths")
+        #Scanning - Removing
+        pars.add_argument("--remove_relative", type=inkex.Boolean, default=False, help="relative cmd")
+        pars.add_argument("--remove_absolute", type=inkex.Boolean, default=False, help="absolute cmd")
+        pars.add_argument("--remove_mixed", type=inkex.Boolean, default=False, help="mixed cmd (relative + absolute)")
+        pars.add_argument("--remove_polylines", type=inkex.Boolean, default=False, help="polyline")
+        pars.add_argument("--remove_beziers", type=inkex.Boolean, default=False, help="bezier")
+        pars.add_argument("--remove_opened", type=inkex.Boolean, default=False, help="opened")
+        pars.add_argument("--remove_closed", type=inkex.Boolean, default=False, help="closed")
+        pars.add_argument("--remove_self_intersecting", type=inkex.Boolean, default=False, help="self-intersecting")
 
-       #Scanning - Highlighting
-        pars.add_argument("--highlight_relative", type=inkex.Boolean, default=False, help="Highlight relative cmd paths")
-        pars.add_argument("--highlight_absolute", type=inkex.Boolean, default=False, help="Highlight absolute cmd paths")
-        pars.add_argument("--highlight_mixed", type=inkex.Boolean, default=False, help="Highlight mixed cmd (relative + absolute) paths")
-        pars.add_argument("--highlight_polylines", type=inkex.Boolean, default=False, help="Highlight polyline paths")
-        pars.add_argument("--highlight_beziers", type=inkex.Boolean, default=False, help="Highlight bezier paths")
-        pars.add_argument("--highlight_opened", type=inkex.Boolean, default=False, help="Highlight opened paths")
-        pars.add_argument("--highlight_closed", type=inkex.Boolean, default=False, help="Highlight closed paths")
-        pars.add_argument("--highlight_self_intersecting", type=inkex.Boolean, default=False, help="Highlight self-intersecting contours")
+        #Scanning - Highlighting
+        pars.add_argument("--highlight_relative", type=inkex.Boolean, default=False, help="relative cmd paths")
+        pars.add_argument("--highlight_absolute", type=inkex.Boolean, default=False, help="absolute cmd paths")
+        pars.add_argument("--highlight_mixed", type=inkex.Boolean, default=False, help="mixed cmd (relative + absolute) paths")
+        pars.add_argument("--highlight_polylines", type=inkex.Boolean, default=False, help="polyline paths")
+        pars.add_argument("--highlight_beziers", type=inkex.Boolean, default=False, help="bezier paths")
+        pars.add_argument("--highlight_opened", type=inkex.Boolean, default=False, help="opened paths")
+        pars.add_argument("--highlight_closed", type=inkex.Boolean, default=False, help="closed paths")
+        pars.add_argument("--highlight_self_intersecting", type=inkex.Boolean, default=False, help="self-intersecting paths")
         pars.add_argument("--draw_subsplit", type=inkex.Boolean, default=False, help="Draw sub split lines (polylines)")
-        pars.add_argument("--visualize_self_intersections", type=inkex.Boolean, default=False, help="Visualize self-intersecting path points")
-        pars.add_argument("--visualize_global_intersections", type=inkex.Boolean, default=False, help="Visualize global intersection points")
+        pars.add_argument("--visualize_self_intersections", type=inkex.Boolean, default=False, help="self-intersecting path points")
+        pars.add_argument("--visualize_global_intersections", type=inkex.Boolean, default=False, help="global intersection points")
  
-        #Settings - Trimming      
+        #Settings - Trimming
         pars.add_argument("--draw_trimmed", type=inkex.Boolean, default=False, help="Draw trimmed lines")
         pars.add_argument("--combine_nonintersects", type=inkex.Boolean, default=True, help="Combine non-intersected lines")
         pars.add_argument("--remove_duplicates", type=inkex.Boolean, default=True, help="Remove duplicate trim lines")
@@ -442,22 +448,22 @@ class ContourScannerAndTrimmer(inkex.EffectExtension):
         pars.add_argument("--apply_original_style", type=inkex.Boolean, default=True, help="Apply original path style to trimmed lines")
      
         #Style - Scanning Colors
-        pars.add_argument("--color_subsplit", type=Color, default='1630897151', help="Color for sub split lines")
-        pars.add_argument("--color_relative", type=Color, default='3419879935', help="Color for relative cmd paths")
-        pars.add_argument("--color_absolute", type=Color, default='1592519679', help="Color for absolute cmd paths")
-        pars.add_argument("--color_mixed", type=Color, default='3351636735', help="Color for mixed cmd (relative + absolute) paths")
-        pars.add_argument("--color_polyline", type=Color, default='4289703935', help="Color for polyline paths")
-        pars.add_argument("--color_bezier", type=Color, default='258744063', help="Color for bezier paths")
-        pars.add_argument("--color_opened", type=Color, default='4012452351', help="Color for opened paths")
-        pars.add_argument("--color_closed", type=Color, default='2330080511', help="Color for closed paths")
-        pars.add_argument("--color_self_intersecting_paths", type=Color, default='2593756927', help="Color for self-intersecting contours")
-        pars.add_argument("--color_self_intersections", type=Color, default='6320383', help="Color for self-intersecting line points")
-        pars.add_argument("--color_global_intersections", type=Color, default='4239343359', help="Color for global intersection points")
+        pars.add_argument("--color_subsplit", type=Color, default='1630897151', help="sub split lines")
+        pars.add_argument("--color_relative", type=Color, default='3419879935', help="relative cmd paths")
+        pars.add_argument("--color_absolute", type=Color, default='1592519679', help="absolute cmd paths")
+        pars.add_argument("--color_mixed", type=Color, default='3351636735', help="mixed cmd (relative + absolute) paths")
+        pars.add_argument("--color_polyline", type=Color, default='4289703935', help="polyline paths")
+        pars.add_argument("--color_bezier", type=Color, default='258744063', help="bezier paths")
+        pars.add_argument("--color_opened", type=Color, default='4012452351', help="opened paths")
+        pars.add_argument("--color_closed", type=Color, default='2330080511', help="closed paths")
+        pars.add_argument("--color_self_intersecting_paths", type=Color, default='2593756927', help="self-intersecting paths")
+        pars.add_argument("--color_self_intersections", type=Color, default='6320383', help="self-intersecting path points")
+        pars.add_argument("--color_global_intersections", type=Color, default='4239343359', help="global intersection points")
        
         #Style - Trimming Color
-        pars.add_argument("--color_trimmed", type=Color, default='1923076095', help="Color for trimmed lines")
-        pars.add_argument("--color_combined", type=Color, default='3227634687', help="Color for non-intersected lines")
-        pars.add_argument("--color_nonintersected", type=Color, default='3045284607', help="Color for non-intersected paths")
+        pars.add_argument("--color_trimmed", type=Color, default='1923076095', help="trimmed lines")
+        pars.add_argument("--color_combined", type=Color, default='3227634687', help="non-intersected lines")
+        pars.add_argument("--color_nonintersected", type=Color, default='3045284607', help="non-intersected paths")
 
 
     def effect(self):
@@ -506,6 +512,7 @@ class ContourScannerAndTrimmer(inkex.EffectExtension):
         allSubSplitStyles = []
         allSubSplitIsBezier = []
         allSubSplitOriginalPathIds = []
+        allSubSplitIsClosed = []
         
         allSubSplitData = [] #an array of sub split lines and it's belonging sub path id
         allSubSplitData.append(allSubSplitLines) #column 0
@@ -513,6 +520,7 @@ class ContourScannerAndTrimmer(inkex.EffectExtension):
         allSubSplitData.append(allSubSplitStyles) #column 2
         allSubSplitData.append(allSubSplitIsBezier) #column 3
         allSubSplitData.append(allSubSplitOriginalPathIds) #column 4
+        allSubSplitData.append(allSubSplitIsClosed) #column 5
 
         for pathElement in pathElements:
             path = pathElement.path.transform(pathElement.composed_transform())
@@ -538,11 +546,6 @@ class ContourScannerAndTrimmer(inkex.EffectExtension):
             if so.remove_closed is True and isClosed is True:
                 pathElement.delete()
                 continue #skip this loop iteration
-            
-            #Check if we should skip or process the path anyway   
-            if so.path_types == 'open_paths' and isClosed is True: continue #skip this loop iteration
-            elif so.path_types == 'closed_paths' and isClosed is False: continue #skip this loop iteration
-            elif so.path_types == 'both': pass
 
             #check for relative or absolute paths. Does not work if break apart is enabled
             isRelative = False
@@ -632,6 +635,7 @@ class ContourScannerAndTrimmer(inkex.EffectExtension):
                 subSplitStyles = []
                 subSplitIsBezier = []
                 subSplitOriginalPathIds = []
+                subSplitIsClosed = []
                 for i in range(len(segs) - 1): #we could do the same routine to build up polylines using "for x, y in node.path.end_points". See "number nodes" extension
                     x1, y1, x2, y2 = self.lineFromSegments(segs, i, so.decimals)
                     #self.msg("(y1 = {},y2 = {},x1 = {},x2 = {})".format(x1, y1, x2, y2))
@@ -655,6 +659,7 @@ class ContourScannerAndTrimmer(inkex.EffectExtension):
                     subSplitStyles.append(pathElement.style)
                     subSplitIsBezier.append(isBezier) #some dirty flag we need
                     subSplitOriginalPathIds.append(originalPathId) #some dirty flag we need
+                    subSplitIsClosed.append(isClosed) #some dirty flag we need
 
                 if deleteFlag is True:
                     pathElement.delete()
@@ -724,12 +729,14 @@ class ContourScannerAndTrimmer(inkex.EffectExtension):
                     subSplitIds != None and \
                     subSplitStyles != None and \
                     subSplitIsBezier != None and \
-                    allSubSplitOriginalPathIds != None:
+                    allSubSplitOriginalPathIds != None and \
+                    allSubSplitIsClosed != None:
                     allSubSplitStyles.extend(subSplitStyles)
                     allSubSplitLines.extend(subSplitLines)
                     allSubSplitIds.extend(subSplitIds)
                     allSubSplitIsBezier.extend(subSplitIsBezier)
                     allSubSplitOriginalPathIds.extend(subSplitOriginalPathIds)
+                    allSubSplitIsClosed.extend(subSplitIsClosed)
 
             if so.draw_subsplit is True:
                 if subSplitTrimLineGroup is not None: #might get deleted before so we need to check this first
@@ -754,14 +761,13 @@ class ContourScannerAndTrimmer(inkex.EffectExtension):
                 We do this path by path to keep the logic between original paths, sub split lines and the final output
                 '''
                 if so.draw_trimmed is True:
-                    allTrimGroups = [] #container to collect all trim groups for later on processing
-                    trimLineIndex = 1  
+                    allTrimGroups = [] #container to collect all trim groups for later on processing 
                     for subSplitIndex in range(len(allSubSplitData[0])):
                         trimGroup = self.buildTrimLineGroups(allSubSplitData, subSplitIndex, 
-                            globalIntersectionPoints, trimLineIndex, so.snap_tolerance, so.apply_original_style)
-                        if trimGroup not in allTrimGroups:
-                            allTrimGroups.append(trimGroup)
-                        trimLineIndex += 1
+                            globalIntersectionPoints, so.snap_tolerance, so.apply_original_style)
+                        if trimGroup is not None:
+                            if trimGroup not in allTrimGroups:
+                                allTrimGroups.append(trimGroup)
                  
                     if so.show_debug is True: self.msg("trim groups count: {}".format(len(allTrimGroups)))
                     if len(allTrimGroups) == 0: