In the past i was looking for POV-Ray GUI and found LEGO community and variety of apps intended for LEGO work:
There are apps (Linux included) for using POV-Ray too (LDview). It is interesting LDview does support creating bottom plane on the fly (something we disused when talking about POV-Ray support in FreeCAD).
http://www.eurobricks.com/forum/index.p ... opic=65876
Maybe when assembly workbench lands FreeCAD will gain a few users doing stuff like this in FreeCAD. About direct support built in FreeCAD i did not investigate legal stuff.