Canderis

Oh, found something else, that might "save" your model: for that low, euh strip along the walls. Is by adding in extra verts and connecting them, just like the stuff from my previous message: So in editable poly, select by edge, look for Insert Vertex (1); click along to add in extra verts. Then scroll down for CREATE (2) and connect your new made verts with the older ones:

Did the same for those round corners at the end/ entrance to the round room.

Now these last dudes, could have been the cause of trouble, though, its still iffy.

Other then a few smallish clean up issues, I couldn't find anything that was wrong.