By now:
Example workbench with just a command (geometry) which creates a line from origin (0,0,0) to the middle of the selected face.
If no selection while creation: Exception!!
Main properties: created line links object. It means:
- line is deleted if you delete the object
- line is updated if you edit object
Howto install:
- just copy the GDTWB dir to /usr/lib/freecad/Mod/
- restart FreeCAD!