Demo not working
 

I downloaded the demo and installed it. But when I hit play on the set up and it pulled up the page with news and two buttons, update and play. When I hit play, the game tries to load, the screen goes black and the mouse changes to the game version. But instead of loading completely, it shuts down, send back to the desktop, and the screen saying thank for playing pops back up, with only one button, buy now. Any help?