Consider switching to 64-bit
MS .NET 3.5 installer now works in 64-bit, so enforcing this is no longer necessary. In fact, Livesplit needs to run in a 64-bit prefix because it uses so much memory.
We do not want to enact this if we are on a broken Winetricks version. I don't know how we can possibly test for this, I guess we could take code from Winetricks?