this can happen when the game isn\'t happy with the resolution. the mouse is being rendered away from it\'s actual location. move it around untill a button hilights, spawn, hit esc, go to options and click \"vert sync\". note that all this time it can be dificult to know where you\'r mouse is, for me it renders to the right of it\'s actual location. once \"vert sync\" is on (or off if it was on already) and you press ok, the screen should re-align and the mouse should render in the right location. also, I have found that I have to do this every time I play, and that setting \"vert sync\" before starting it up dosn\'t help, I still have to toggle it later.
this bug does not happen on every computer, and, as I said, seems to be tied to screen resolution