Until it builds a stairway which leads to an attic in such a way that the access is under the shallowest part of the roof and unusable.

I've tried using the 3D generation stuff a bit, but it never worked out.

Still amazed that folks such as:

https://www.reddit.com/r/openscad/comments/1adcw41/i_am_comp...

manage to get anything usable in 3D at all, but making an STL is a big difference from making a useful architectural structure.