Thank you for the fast answer and the file explaining how this then looks like.
I have tried this method out now but I fear that my project is just a bit too complicated since I have some only 1.4 m high walls separating e.g. kitchen from living room and of course, the programme then tries to attach ...

For an attic renovation project, I am wondering if there were any way to make ceilings that are not horizontal but inclined like the inner side of a roof with windows etc.
If not, are there any plans to add this feature to this so far fabulous programme?

thanks for any hints / answers

Leopold