Have you installed the path?
if not, here it is
http://www.gamefront.com/files/files/15186509/saboteur_patch_1.03beta.zip and the changelog
The Saboteur(tm)
Version 1.03 BETA Patch Notes - December 18, 2009
==================================================================
Game no longer freezes during play on the following hardware
combination:
* ATI video card from the 3K, 4K, and 5K series
* Windows Vista/7 both 32 bit and 64 bit
Known Issues & Current Workaround:
Users with Quad core CPU's will possibly have significant streaming issues without the following work around. The team is aware of this issue and is working on a fix for it in the next patch update. If you are running a Quad Core CPU please follow the steps below to set Game Only affinity on your CPU. While this will decrease the amount of streaming glitches, it is not a full proof fix.
Recommended Game-only steps for Quad core users only:
Windows 7 and Vista
1.) Boot the game.
2.) Wait for the main menu to load, then press Ctrl-Alt-Delete.
3.) Select Start Task Manager.
4.) If the game is visible, press Alt-Tab, otherwise continue to the next step.
5.) Inside the Task Manager, go to the Processes tab.
6.) Find Saboteur.exe, right-click it, and select Set Affinity
7.) De-select CPU 2 and CPU 3.
8.) Click OK.