Hi Daniele!
Let's start with good news: WORK!!!
After few modifications (work only with rooms in clock wise) and I fix it.
Work with ALL my files used for test including some improbably shape.
Now some TODO:
-this version is the stable one which don't allow negative value for weight (like we see in the demo video).
I have both and I'll try to update current files You have share.
-somewhere in org.twak.utils is a import_obj.py file used to import obj+mtl files in Blender.
That's mean somewhere this files are generated. I'll see where.
If so is all I need to pass them to exportObject(). It's too good to be true!
-for 3D I've see this in src.
All this mean I've have to start work from 0 the roof plugin and it's OK.

Thanks again for priceless help!!
Dorin