Map related game freeze.

[Demolution]

Every time I load Karith, and I start moving as a spectator the game immediately freezes. So far this happens only for Karith and one other map (only once though). I can avoid the freeze for a while if I join a team, but it eventually freezes. I think around the human's base...
If I have music playing, the music doesn't stop, nor do any other processes/programs.
When the game freezes I can manage to get the Task Manager, and tell it to close Trem, but it never does. The only remedy so far is to restart my computer manually.
I have a laptop that runs Vista. All of my drivers are up to date. I have had graphics issues before, but nothing as selective as this.

P.S. I can't remember the name of the other map, but it was much bigger than Karith and had a pretty good fps drain. It's the map with a star map on the load screen.

[Lava Croft]

P.S. I can't remember the name of the other map, but it was much bigger than Karith and had a pretty good fps drain. It's the map with a star map on the load screen.

Procyon? Or another one of Ingar's maps?

[Demolution]

Yeah, it was Procyon, but it froze only once. And also I am missing some textures on a few of the usual maps. Should I reinstall? Or could I find a quicker fix by replacing some file(s)?