I've got CS:S installed through Steam on Snow Leopard on a Core Duo iMac (Radeon X1600.) The mouse acceleration just plain doesn't feel right, and it's like the mouse lags. In the preferences I can't set it to use raw input, the option is grayed out. I know that in the Windows version of Unreal Tournament I had a similar problem until I told it to use "Direct Input", so I assume that by enabling "Raw Input" in CS:S in OS X it should fix my problem. Any ideas?