Things that are making Thief look better...
- (In game menu) Go to resolution in options and put 1024x768x16.
If you haven't got sound...
- (In game menu) Options/Sound: Turn off the hardware acceleration.
If your game works too fast...
- (In windows) R-Click on your .exe to Thief and put other compatibility, try Service Pack.
- (In windows) CPU Speed Adjuster - This program will allow you to slow down too strong processor, so that your Thief will slow down.
If there are other problems...
Just write.
Sorry but I can't help you with Thief download, maybe someone other.