If you're using IE and the wmode is set to transparent/opaque then IE will not focus correctly on the Flash Movie. My problem lies in that I have a game with Up/Down input commands, now if wmode is transparent or opaque pressing Up/Down will move the whole page. If I change it to window or remove it then it'll work fine.
It only happens in IE, it works fine in Firefox. Also I need to use transparent or opaque because I have a game summary that pops up at the end of the game which is held in a lightbox, hence the need.