I bought the bundle and had the same problem... I didn't realize that all the DLC(Including Rearmed) comes down from Steam automatically. I have Arma II : CO from Amazon and it was not fully updated(Ver. 1.59). I downloaded the three newest patches to get me up to date. After that, the game is now running. I'm still having problems with certain parts of the game not loading... I don't think that is related though. For example I cannot load the first training flight.