I've just downloaded DoomIII, and now I can't play the thing! I start off good enough, but for some reason I'm not able to set any options. I thought "I'll worry about that later.", so I went into single player mode, but as it starts loading, that's it. The screen says, 'Loading', but nothing else is happening. At first I thought that I was low on resources, so I rebooted, and tried again. This time I let it load for a bit, but 10(!!) minutes later, still nothing. Please help! Could it be my pc, or the game itself.