Thank you. That is a atlas problem , in game. That only Joscha can fix. But if you play default game , it should work. At that problem a atlas not works correct. and at moment there is a bug there at atlas's , that is still not fixed. but in standart game (not edge) it works

That is a game bug , that is already fixed in edge , in default that bug is still there. So the best is to switch to edge , then it works.

if i use the floors, random walls and floors dissapear closeby
wth?

I have checked that , that is normal , it have the same behavior like the in-game floors. You just can remove it by building a new floor on it , or you must dismantle the fountaintion. It is the same like at the ingame floors . Only the bar concrete not works , but at all mod floors. Walls work there also.

I can't remove floor 78 (I didn't try any other floors) with bare concrete or by building walls/other floors (03B) over it.