For some reason three of the acheivments will not unlock for me. The acheivement with the Koala, the big fish and the ending where you shot the deer after the boss fight. Ironically the game itself says I have unlocked all the acheivements (when I go into settings), and the Xbox poppet the 100 gamer score acheivements for acheiving all the acheivements of the game. Strange ...