diff --git a/FileLoading.pde b/FileLoading.pde
index b8217a2..73a7bfb 100644
--- a/FileLoading.pde
+++ b/FileLoading.pde
@@ -322,6 +322,9 @@ RShape loadShapeFromGCodeFile(String filename) {
             drawLine = false;
           }
         }
+        else { //  if there is no Z axis, assume it's always on
+//          drawLine = true; // this isn't always safe!
+        }        
         
         Float x = ins.get("X");
         Float y = ins.get("Y");
diff --git a/README.md b/README.md
index 6c68d9e..e51a596 100644
--- a/README.md
+++ b/README.md
@@ -13,5 +13,7 @@ This is a desktop application for controlling a polargraph machine, communicatin
 The [latest releases bundle] (https://github.com/euphy/polargraphcontroller/releases/latest) contains 
 copies of all the libraries that I use, as well as all the source, and compiled versions of the code where sensible.
 
+How to [run it from source](https://github.com/euphy/polargraph/wiki/Running-the-controller-from-source-code).
+
 sandy.noble@gmail.com
 http://www.polargraph.co.uk/