mouse not working and game lag

[dan,lei]

hi guys just a quick question, need some help.

my mouse when the game is loaded is no where to be seen on the screen and the game is lagging. I'm running windows 8 and pondering if that's anything to do with the problem? the mouse is normally fine, the computer is fine, I run the game and everything freezes?! I've ran it as admin, I've got a graphics card that's better than what is needed and I've also checked the game integrity cache. is it windows 8 or what? I've downloaded the game off steam.

any help appreciated![/font]