BIG PLUS~ at least for me...
Game did not work at first, but instead of complaining about how it didn't work yadadada...
-Update your drivers, i have a radeon driver, updated it (which I had never done before) and tada! It worked.
-Move it to the C:/ or wherever your steam is, cause I did that although I think updating the driver was the most important
-Be prepared for the lag, 30 fps or whatnot, there is lag involved, at least for the first couple hours of playing it, although it eventually straightened out by itself.