I got the demo this afternoon through Steam and absolutely loved it, then the message popped up telling me I can't play the demo anymore. So I went and bought the full game through Steam. But now when I try and play the game, that same message comes up as did in the demo, telling me I have to buy the game. I already did buy the game! Yes I am running the full version, as the demo no longer appears in the 'My Games' Steam tab.
Please help!