A note for the floors. - Try disconnecting from live completely (pull out the cord) and forging in local there. I did that on my last zombie map and it really helped keep the walls straight, even after save and quit. Saving and quitting while connected to live is very annoying if you ask me, even after the floor is built.
annoying, i know, escpecially for a neat freak. I spent alot of time lining it up when it was only off by an incrediply small amount an it bounced back out next time i play
Thanks for the help guys but I have tried this and still the same result, I think it has to do with the block doubles as walls propping them up.