Another thing, before I create an icon, I always check if the game can run through a terminal execution (often in root). But with Angry BIrds, it's a bad idea : it creates "settings.lua" and "highscores.lua" files with unappropriate permissions for non-root user and it makes that the game can't start anymore for a non-root user (it is always possible to fix this issue by a "chmod" command).