Hi tim,
Can you be more specific? Is the game window not loading completely? Do you not see the game window pop-up at all?
Typically most loading issues can be solved by clearing your flash and browser caches. Clearing your caches allows your PC to obtain the most recently updated files from the server. Sometimes outdated or corrupted files in the cache can cause the game to error when it loads. After you clear your caches be sure to reset any in-game options you prefer like graphics quality or flagstick animations.
If clearing your caches doesn't solve the problem please let us know.