describe us your problems… and add your hardware and software configurations
in the recent past someone have meet problems for different causes, my problems depends probably from some firefox interference… Sandy had problems with a corrupted installation and sosorita had problems for the video card drivers… if you have problems during the launch of the application, probably your problems are from an interaction to your achat installation with some other program… search to start your achat before of other programs…
if your problem is during the game, maybe is a problem bound at your video card or video drivers…
in every case, a reinstall can be a good idea
obviusly you don't lost nothing of your account, your data are in the server