Hi, i have suffered the same issue with complex drawing and the problem still continue, but i can move forward using the next strategy:

1 create every floor in ground level 2 identify wich floor and or roof are adiabatic and change to adiabatic manually 3 identify floor and or roof exposed and change to exposed manually 4 assemble floors simulating your real buildingmanually

This strategy is an approach but to me works good.

Tell me if work for you!!!