Having recently bought this game from impulse and installed it i fired it up to get a popup window asking for a serial number. Ive copied and pasted the one provided/hand written it and tried other opyions but it wont hold. If i enter the correct serial number the window clears out and resets the serial number entry part blank without me hitting enter at all. If i enter the wrong one nothing happens uuntil i hit enter then i get a beep.

Please explain what i am doing wrong as i would like to play the game

ps your serial number entry window has no way to be closed and insists on being on top which is fairly annoying when its broken