So I bought CoD 4 for my Mac a while ago, on disc, and then it became unplayable once I moved to Snow Leopard, which the developers weren't going to do anything about. The version in the App Store requires Snow Leopard, so I presume it's a newer version. The problem is that it refuses to call my copy 'Installed' on the store, so I can't update or anything. Basically all I want to do is be able to play MW on my Mac, without buying it again from the Mac App Store. Any ideas?