diff --git a/README.md b/README.md
index ee9b9f1..3267321 100644
--- a/README.md
+++ b/README.md
@@ -2,7 +2,7 @@
 
 <img title="" src="./extensions/fablabchemnitz/000_Mightyscape.svg" alt="" data-align="left">
 
-In short: A maintained extension collection for Inkscape 1.2, working on Windows and Linux. There are **237 extension folders** with **432 .inx files** inside. We also take part at https://inkscape.org/gallery/=extension/ (with single extension uploads).
+In short: A maintained extension collection for Inkscape 1.2, working on Windows and Linux. There are **239 extension folders** with **459 .inx files** inside. We also take part at https://inkscape.org/gallery/=extension/ (with single extension uploads).
 
 # About MightyScape
 
diff --git a/extensions/fablabchemnitz/apply_transformations/apply_transformations.py b/extensions/fablabchemnitz/apply_transformations/apply_transformations.py
index e864953..9290d77 100644
--- a/extensions/fablabchemnitz/apply_transformations/apply_transformations.py
+++ b/extensions/fablabchemnitz/apply_transformations/apply_transformations.py
@@ -141,10 +141,7 @@ class ApplyTransformations(inkex.EffectExtension):
                 or not isequal(newxy2[0], newxy3[0])
                 or not isequal(newxy1[1], newxy2[1])
             ):
-                inkex.utils.errormsg(
-                    "Warning: Shape %s (%s) is approximate only, try Object to path first for better results"
-                    % (element.TAG, element.get("id"))
-                )
+                inkex.utils.errormsg(f"Warning: Shape {node.TAG} ({node.get('id')}) is approximate only, try Object to path first for better results")
 
             if element.TAG == "ellipse":
                 element.set("rx", edgex / 2)
@@ -204,10 +201,7 @@ class ApplyTransformations(inkex.EffectExtension):
                           inkex.addNS('text', 'svg'),
                           inkex.addNS('image', 'svg')]:
             element.attrib['transform'] = str(transf)
-            inkex.utils.errormsg(
-                "Shape %s (%s) not yet supported. Not all transforms will be applied. Try Object to path first"
-                % (element.TAG, element.get("id"))
-            )
+            inkex.utils.errormsg(f"Shape {node.TAG} ({node.get('id')}) not yet supported. Not all transforms will be applied. Try Object to path first")
         else:
             # e.g. <g style="...">
             self.scaleStrokeWidth(element, transf)
diff --git a/extensions/fablabchemnitz/box_maker_generic_generator/box_maker_generic_generator.py b/extensions/fablabchemnitz/box_maker_generic_generator/box_maker_generic_generator.py
index 1f7a5af..f976612 100644
--- a/extensions/fablabchemnitz/box_maker_generic_generator/box_maker_generic_generator.py
+++ b/extensions/fablabchemnitz/box_maker_generic_generator/box_maker_generic_generator.py
@@ -1540,7 +1540,8 @@ class BoxFace:
         InteriorHeight = self.bottom_right_corner.y_end_joint * Height_percentage / 100.0
         l_NotchLine = NotchLine((0, 0, 1), (InteriorHeight, 0, 1), math.pi/2, z_joint_size) 
 
-        StartHole = l_NotchLine.start_line_joint_y + l_NotchLine.JointSize
+        #First hole z computation. Start at notch line but add delta if Height_percentage is not 100%
+        StartHole = l_NotchLine.start_line_joint_y + l_NotchLine.JointSize + self.bottom_right_corner.y_end_joint - InteriorHeight
         Spacing = 2*l_NotchLine.JointSize
         DebugMsg("drawFaceWithHoles, Hole Start ="+str(StartHole)+" Spacing="+str(Spacing)+" n_holes"+str(l_NotchLine.nb_finger_joint//2)
                  +' n_slot='+str(n_slot)+'  slot_size='+str(slot_size)+" Delta_Pos="+str(DeltaHolePosition)+'\n')
@@ -1548,7 +1549,8 @@ class BoxFace:
             #For each wall, draw holes corresponding at each notch on zbox
             for j in range(int(l_NotchLine.nb_finger_joint//2)):
                 drawHole(self.path, i*(slot_size+thickness) - DeltaHolePosition -thickness, StartHole + j*Spacing, thickness, l_NotchLine.JointSize, burn)
-
+                DebugMsg("drawHole, Slot="+str(i)+", j="+str(j)+", x="+str(i*(slot_size+thickness) - DeltaHolePosition -thickness)+" y="+str(StartHole + j*Spacing)+'\n')
+                
         #Close the path if asked
         if ClosePath:
             self.path.Close()
diff --git a/extensions/fablabchemnitz/dxf2papercraft/meta.json b/extensions/fablabchemnitz/dxf2papercraft/meta.json
index 23df6d3..12715fb 100644
--- a/extensions/fablabchemnitz/dxf2papercraft/meta.json
+++ b/extensions/fablabchemnitz/dxf2papercraft/meta.json
@@ -10,7 +10,7 @@
     "license_url": "https://sourceforge.net/projects/dxf2papercraft/files/dxf2papercraft_v0.2.tgz/download",
     "comment": "Written by Mario Voigt",
     "source_url": "https://gitea.fablabchemnitz.de/FabLab_Chemnitz/mightyscape-1.2/src/branch/master/extensions/fablabchemnitz/dxf2papercraft",
-    "fork_url": "",
+    "fork_url": null,
     "documentation_url": "https://stadtfabrikanten.org/display/IFM/DXF+2+Papercraft",
     "inkscape_gallery_url": "https://inkscape.org/~MarioVoigt/%E2%98%85dxf2papercraft",
     "contributors": [
diff --git a/extensions/fablabchemnitz/label_guides/label_guides.py b/extensions/fablabchemnitz/label_guides/label_guides.py
index 9192110..e28fa8c 100644
--- a/extensions/fablabchemnitz/label_guides/label_guides.py
+++ b/extensions/fablabchemnitz/label_guides/label_guides.py
@@ -428,7 +428,7 @@ class LabelGuides(inkex.Effect):
 
         # Draw horizontal guides
         for g in guides['h']:
-            add_SVG_guide(0, self.svg.viewport_height - g, 'horz', colour, nv)
+            add_SVG_guide(0, self.svg.viewbox_height - g, 'horz', colour, nv)
 
     def _draw_centre_guides(self, document, label_opts, colour):
         """
@@ -444,7 +444,7 @@ class LabelGuides(inkex.Effect):
 
         for g in range(0, len(guides['h']), 2):
             pos = (guides['h'][g] + guides['h'][g + 1]) / 2
-            add_SVG_guide(0, self.svg.viewport_height - pos, 'horz', colour, nv)
+            add_SVG_guide(0, self.svg.viewbox_height - pos, 'horz', colour, nv)
 
     def _draw_shapes(self, document, label_opts, inset):
         """
diff --git a/extensions/fablabchemnitz/open_in_roland_cutstudio/open_in_roland_cutstudio.py b/extensions/fablabchemnitz/open_in_roland_cutstudio/open_in_roland_cutstudio.py
index 3cbbecd..179e0c3 100644
--- a/extensions/fablabchemnitz/open_in_roland_cutstudio/open_in_roland_cutstudio.py
+++ b/extensions/fablabchemnitz/open_in_roland_cutstudio/open_in_roland_cutstudio.py
@@ -22,14 +22,6 @@ along with this program; if not, write to the Free Software
 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 '''
 
-# The source code is a horrible mess. I apologize for your inconvenience, but hope that it still helps. Feel free to improve :-)
-# Keep everything python2 compatible as long as people out there are using Inkscape <= 0.92.4!
-
-from __future__ import division
-from __future__ import print_function
-from __future__ import unicode_literals
-from __future__ import absolute_import
-
 from builtins import open
 from builtins import map
 from builtins import str
@@ -57,6 +49,11 @@ import string
 
 DEVNULL = open(os.devnull, 'w')
 atexit.register(DEVNULL.close)
+# work around Inkscape 1.3 failing to start when it "calls itself" (Inkscape -> Extension -> Inkscape):
+# https://gitlab.com/inkscape/inkscape/-/issues/4163
+# https://gitlab.com/inkscape/extensions/-/merge_requests/534
+# TODO: Rewrite most parts of this extension using the inkex python module. This removes the need for such workarounds.
+os.environ["SELF_CALL"] = "true"
 
 def message(s):
     sys.stderr.write(s+"\n")
@@ -71,9 +68,9 @@ def which(program, raiseError, extraPaths=[], subdir=None):
     """
     pathlist=os.environ["PATH"].split(os.pathsep)
     if "nt" in os.name:
-        pathlist.append(os.environ.get("ProgramFiles","C:\Program Files\\"))
-        pathlist.append(os.environ.get("ProgramFiles(x86)","C:\Program Files (x86)\\"))
-        pathlist.append("C:\Program Files\\") # needed for 64bit inkscape on 64bit Win7 machines
+        pathlist.append(os.environ.get('ProgramFiles','C:\\Program Files\\'))
+        pathlist.append(os.environ.get('ProgramFiles(x86)','C:\\Program Files (x86)\\'))
+        pathlist.append('C:\\Program Files\\') # needed for 64bit inkscape on 64bit Win7 machines
         pathlist.append(os.path.dirname(os.path.dirname(os.getcwd()))) # portable application in the current directory
     pathlist += extraPaths
     if subdir:
@@ -286,8 +283,8 @@ def EPS2CutstudioEPS(src, dest, mirror=False):
         m=m.transpose()
         #debug("with {}".format(m))
         pnew = numpy.matmul(m, p)
-        x=float(pnew[0])
-        y=float(pnew[1])
+        x=float(pnew.item(0))
+        y=float(pnew.item(1))
         #debug("to: {} {}".format(x, y))
         return [x, y]
     def outputMoveto(x, y):
@@ -410,7 +407,7 @@ if "--selftest" in sys.argv:
 
 if os.name=="nt":
     DETACHED_PROCESS = 8 # start as "daemon"
-    Popen([which("CutStudio\CutStudio.exe", True), "/import", destination], creationflags=DETACHED_PROCESS, close_fds=True)
+    Popen([which("CutStudio\\CutStudio.exe", True), "/import", destination], creationflags=DETACHED_PROCESS, close_fds=True)
 else: #check if we have access to "wine"
     CUTSTUDIO_C_DRIVE = str(Path.home()) + "/.wine/drive_c/"
     CUTSTUDIO_PATH_LINUX_WINE = CUTSTUDIO_C_DRIVE + "Program Files (x86)/CutStudio/CutStudio.exe"
diff --git a/extensions/fablabchemnitz/pixel2svg/meta.json b/extensions/fablabchemnitz/pixel2svg/meta.json
index effffef..537edc5 100644
--- a/extensions/fablabchemnitz/pixel2svg/meta.json
+++ b/extensions/fablabchemnitz/pixel2svg/meta.json
@@ -10,7 +10,7 @@
     "license_url": "https://gitlab.com/su-v/inx-pixel2svg/-/blob/master/COPYING",
     "comment": "ported to Inkscape v1 manually by Mario Voigt",
     "source_url": "https://gitea.fablabchemnitz.de/FabLab_Chemnitz/mightyscape-1.2/src/branch/master/extensions/fablabchemnitz/pixel2svg",
-    "fork_url": "ttps://gitlab.com/su-v/inx-pixel2svg",
+    "fork_url": "https://gitlab.com/su-v/inx-pixel2svg",
     "documentation_url": "https://stadtfabrikanten.org/display/IFM/Pixel2SVG",
     "inkscape_gallery_url": null,
     "contributors": [
diff --git a/extensions/fablabchemnitz/raster_perspective/raster_perspective.py b/extensions/fablabchemnitz/raster_perspective/raster_perspective.py
index 95c223d..d1776e9 100644
--- a/extensions/fablabchemnitz/raster_perspective/raster_perspective.py
+++ b/extensions/fablabchemnitz/raster_perspective/raster_perspective.py
@@ -80,9 +80,10 @@ class RasterPerspective(inkex.Effect):
         if str(envelope_node) == "image" and str(the_image_node) == "path":
             envelope_node, the_image_node = self.svg.selection #switch
 
-        if str(the_image_node) != "image" and str(envelope_node) != "path":
-            inkex.utils.debug(WARN)
-            return
+        if str(the_image_node) != "image" or str(envelope_node) != "path":
+            inkex.errormsg(WARN)
+            exit()
+
         img_width, img_height = the_image_node.width, the_image_node.height
 
         try:
diff --git a/extensions/fablabchemnitz/shapes/meta.json b/extensions/fablabchemnitz/shapes/meta.json
index 3b19d6e..5088b76 100644
--- a/extensions/fablabchemnitz/shapes/meta.json
+++ b/extensions/fablabchemnitz/shapes/meta.json
@@ -7,10 +7,10 @@
     "original_name": "Shapes for 1.0",
     "original_id": "org.inkscape.effect.shapes1",
     "license": "GNU GPL v2",
-    "license_url": "https://www.arakne.es/wp-content/uploads/2017/08/arakne_shapes_1.zip",
+    "license_url": "https://www.arakne.es/inkscape-shapes-nueva-version-compatible-con-inkscape-1-2",
     "comment": "",
     "source_url": "https://gitea.fablabchemnitz.de/FabLab_Chemnitz/mightyscape-1.2/src/branch/master/extensions/fablabchemnitz/shapes",
-    "fork_url": "https://www.arakne.es/en/inkscape-1-0-shapes-extension-new-version/",
+    "fork_url": "https://www.arakne.es/inkscape-shapes-nueva-version-compatible-con-inkscape-1-2",
     "documentation_url": "https://stadtfabrikanten.org/display/IFM/Shapes",
     "inkscape_gallery_url": null,
     "contributors": [
diff --git a/extensions/fablabchemnitz/sine_and_lace/meta.json b/extensions/fablabchemnitz/sine_and_lace/meta.json
index 782d6c3..f188952 100644
--- a/extensions/fablabchemnitz/sine_and_lace/meta.json
+++ b/extensions/fablabchemnitz/sine_and_lace/meta.json
@@ -1,20 +1,20 @@
 [
   {
-    "name": "Slic3r STL Input",
-    "id": "fablabchemnitz.de.slic3r_stl_input",
-    "path": "slic3r_stl_input",
+    "name": "Sine And Lace",
+    "id": "fablabchemnitz.de.sine_and_lace",
+    "path": "sine_and_lace",
     "dependent_extensions": null,
-    "original_name": "STL Input",
-    "original_id": "com.github.jnweiger.inkscape.input.stl",
-    "license": "GNU GPL v2",
-    "license_url": "https://github.com/jnweiger/inkscape-input-stl/blob/master/LICENSE",
+    "original_name": "Sine and Lace",
+    "original_id": "command.experiment.sineandlace",
+    "license": "GNU GPL v3",
+    "license_url": "https://github.com/evil-mad/EggBot/blob/master/LICENSE",
     "comment": "",
-    "source_url": "https://gitea.fablabchemnitz.de/FabLab_Chemnitz/mightyscape-1.2/src/branch/master/extensions/fablabchemnitz/slic3r_stl_input",
-    "fork_url": "https://github.com/jnweiger/inkscape-input-stl",
-    "documentation_url": "https://stadtfabrikanten.org/display/IFM/Slic3r+STL+Input",
+    "source_url": "https://gitea.fablabchemnitz.de/FabLab_Chemnitz/mightyscape-1.2/src/branch/master/extensions/fablabchemnitz/sine_and_lace",
+    "fork_url": "https://github.com/evil-mad/EggBot",
+    "documentation_url": "https://stadtfabrikanten.org/display/IFM/Sine+And+Lace",
     "inkscape_gallery_url": null,
     "contributors": [
-      "github.com/jnweiger",
+      "github.com/evil-mad",
       "github.com/eridur-de"
     ]
   }
diff --git a/extensions/fablabchemnitz/stroke_font_creator/render_stroke_font_text.inx b/extensions/fablabchemnitz/stroke_font_creator/render_stroke_font_text.inx
index 8940d0d..91eb2af 100644
--- a/extensions/fablabchemnitz/stroke_font_creator/render_stroke_font_text.inx
+++ b/extensions/fablabchemnitz/stroke_font_creator/render_stroke_font_text.inx
@@ -44,6 +44,7 @@
             <param name="charSpacing" type="float" min="0" max="100" gui-text="Char Spacing:">1</param>
             <param name="wordSpacing" type="float" min="0" max="100" gui-text="Word Spacing:">1</param>
             <param name="lineSpacing" type="float" min="0" max="100" gui-text="Line Spacing:">1.5</param>
+            <param name="strokeWidthMult" type="float" min = "0" max = "100" _gui-text="Stroke Width:">1</param>
             <param name="flowInBox" type="bool" gui-text="Flow Text in Selected Boxes:">true</param>
             <param name="margin" type="float" min="-999999" max="999999" gui-text="Margin:">5</param>
             <param name="hAlignment" type="optiongroup" appearance="combo" gui-text="Horizontal Alignment:">
diff --git a/extensions/fablabchemnitz/stroke_font_creator/render_stroke_font_text.py b/extensions/fablabchemnitz/stroke_font_creator/render_stroke_font_text.py
index 4c6dca5..536a8f5 100644
--- a/extensions/fablabchemnitz/stroke_font_creator/render_stroke_font_text.py
+++ b/extensions/fablabchemnitz/stroke_font_creator/render_stroke_font_text.py
@@ -150,6 +150,9 @@ class RenderStrokeFontText(Effect):
         addFn('--lineSpacing', action = 'store', type = typeFloat, dest = 'lineSpacing', \
             default = '1.5', help = 'Spacing between the lines')
 
+        addFn('--strokeWidthMult', action = 'store', type = typeFloat, dest = 'strokeWidthMult', \
+            default = '1', help = 'Stroke Width Proportion')
+
         addFn('--flowInBox', action = 'store', type = typeBool, dest = 'flowInBox', \
             default = False, help = 'Fit the text in the selected rectangle objects')
 
@@ -196,7 +199,7 @@ class RenderStrokeFontText(Effect):
 
         extPath = os.path.dirname(os.path.abspath(__file__))
         
-        strokeWidth = 0.02 * fontSize
+        strokeWidth = 0.02 * fontSize * strokeWidthMult
         
         layer = getCurrentLayer(self)
         renderer = InkscapeFontRenderer(layer, getViewCenter(self), strokeWidth)
diff --git a/extensions/fablabchemnitz/sudoku/meta.json b/extensions/fablabchemnitz/sudoku/meta.json
index d716ff4..730b777 100644
--- a/extensions/fablabchemnitz/sudoku/meta.json
+++ b/extensions/fablabchemnitz/sudoku/meta.json
@@ -1,20 +1,20 @@
 [
   {
-    "name": "Sundial Declining",
-    "id": "fablabchemnitz.de.sundial_declining",
-    "path": "sundial_declining",
+    "name": "Sudoku",
+    "id": "fablabchemnitz.de.sudoku",
+    "path": "sudoku",
     "dependent_extensions": null,
-    "original_name": "Sundial",
-    "original_id": "fr.electropol.tableausimple.inkscape",
-    "license": "Public Domain",
-    "license_url": "https://inkscape.org/de/~TomasUrban/%E2%98%85sundial-declining",
+    "original_name": "Sudoku",
+    "original_id": "org.inkscape.render.sudoku",
+    "license": "GNU GPL v3",
+    "license_url": "https://github.com/neocogent/inkscape-sudoku/blob/master/LICENCE",
     "comment": "ported to Inkscape v1 by Mario Voigt",
-    "source_url": "https://gitea.fablabchemnitz.de/FabLab_Chemnitz/mightyscape-1.2/src/branch/master/extensions/fablabchemnitz/sundial_declining",
-    "fork_url": "https://inkscape.org/de/~TomasUrban/%E2%98%85sundial-declining",
-    "documentation_url": "https://stadtfabrikanten.org/display/IFM/Sundial+Declining",
+    "source_url": "https://gitea.fablabchemnitz.de/FabLab_Chemnitz/mightyscape-1.2/src/branch/master/extensions/fablabchemnitz/sudoku",
+    "fork_url": "https://github.com/neocogent/inkscape-sudoku",
+    "documentation_url": "https://stadtfabrikanten.org/display/IFM/Sudoku",
     "inkscape_gallery_url": null,
     "contributors": [
-      "inkscape.org/TomasUrban",
+      "github.com/neocogent",
       "github.com/eridur-de"
     ]
   }
diff --git a/extensions/fablabchemnitz/svg2shenzhen/svg2shenzhen/export.py b/extensions/fablabchemnitz/svg2shenzhen/svg2shenzhen/export.py
index 39fc79a..deb7022 100644
--- a/extensions/fablabchemnitz/svg2shenzhen/svg2shenzhen/export.py
+++ b/extensions/fablabchemnitz/svg2shenzhen/svg2shenzhen/export.py
@@ -15,7 +15,7 @@ from copy import deepcopy
 from inkex import bezier
 from inkex.transforms import Transform
 from pathlib import Path
-
+import re
 
 homePath = str()
 homePath = Path.home()
@@ -276,8 +276,8 @@ class Svg2ShenzhenExport(inkex.Effect):
 
     def setInkscapeScaling(self):
         root = self.document.getroot()
-        height = float(root.get('height').replace("mm", ""))
-        width = float(root.get('width').replace("mm", ""))
+        height = float(re.sub(r'[a-zA-Z]+', "", root.get('height')))
+        width = float(re.sub(r'[a-zA-Z]+', "", root.get('width')))
 
         self.doc_width = width
         self.doc_height = height
@@ -293,8 +293,8 @@ class Svg2ShenzhenExport(inkex.Effect):
 
     def setDocumentSquare(self):
         root = self.document.getroot()
-        height = float(root.attrib['height'].replace("mm", ""))
-        width =  float(root.attrib['width'].replace("mm", ""))
+        height = float(re.sub(r'[a-zA-Z]+', "", root.attrib['height']))
+        width =  float(re.sub(r'[a-zA-Z]+', "", root.attrib['width']))
 
         if (width > height):
             root.attrib['height'] = str(width) + "mm"