Well, every map that have an enemy lags HARD. I mean 
HARD: less than 1FPS, and I can't play... It lags some times during the game, but it still playable. The menu works smooth... Its not my config, I have the specs:
P4v533-MX
P4 1.8GHz
512mb DDR400
GeForce FX5200 - 256MB
Every setting is set to the lowest, the quality of the graphics is awful, so is the lag...
Thank you, I will play it when this problem is solved 
 EDIT
EDIT Now it lags every time I load the game... I can't continue playing...
I set every setting to the best, and the lag is exactly the same, but the graphics are much better...
I am here:
![[Image: screen1xu1.th.jpg]](http://img259.imageshack.us/img259/3216/screen1xu1.th.jpg) 
It's right after the door where you have to pull a lever and run to pass to the other side. Here's a screenshot of that door:
![[Image: screen2mz5.th.jpg]](http://img411.imageshack.us/img411/3228/screen2mz5.th.jpg)