Fix for 2773 and two other minor fixes.

src/Mod/Path/PathScripts/PathArray.py

@@ -65,7 +65,7 @@ class ObjectArray:
 
             # build copies
             basepath = obj.Base.Path
-            output = basepath.toGCode()
+            output = ""
             pl = FreeCAD.Placement()
             if obj.Offset != FreeCAD.Vector():
                 for i in range(obj.Copies):

src/Mod/Path/PathScripts/PathJob.py

@@ -321,6 +321,7 @@ class TaskPanel:
         self.obj.Proxy.onChanged(self.obj, "PostProcessor")
         self.updateTooltips()
 
+        self.form.PathsList.clear()
         for child in self.obj.Group:
             self.form.PathsList.addItem(child.Name)
 

src/Mod/Path/PathScripts/PathMillFace.py

@@ -178,7 +178,7 @@ class ObjectFace:
                 obj.FinishDepth.Value,
                 obj.FinalDepth.Value)
 
-        extraoffset = 1 - obj.PassExtension.Value
+        extraoffset = - obj.PassExtension.Value
         stepover = (self.radius * 2) * (float(obj.StepOver)/100)
         use_zig_zag = obj.UseZigZag
         zig_angle = obj.ZigZagAngle