Change your texture quality. Set it to medium or high. Don't set it to extra. That should fix your problem. Thats a T4M issue for some graphics cards.

Ya it worked when I turned off specular maps (the actual solution on that thread).

Also if you go into the gondola with the last zombie and activate it, the zombie dies and you and whoever is dead get pushed out of the gondola as it moves down. I spawned in the air above the gondola and my friend fell through the map. Found the big fat guy underwater though ;-)

I'm having the problem described here when I try to play: http://ugx-mods.com/forum/index.php?topic=9886.0
It also happens with Nuketown, but Ragnarok (which also uses T4M) works perfectly. Does anybody know how I can fix this?

Every time I try to play this map the whole game crashes on me.

You need to have T4M installed