this happen to me not too long ago today. It was the very first time it happened to.

If the game's still running when your machine comes back up, then it was most likely an automatic low-battery hibernate/sleep as #1 noted.

This is a very strange issue. Go through Stardock support and see if they can help you....aside from that, I dunno if it is a laptop issue or just a general problem. I tend to agree with Sacrificial_Soul, but it seems like that isn't the problem. Just a random question, do you have an option on your laptop's scrollbar (or whatever it is called; the bar at the bottom of the computer screen, with your running applications on it) and look in the icons next to the clock in the bottom right and see if their is one called power management or something? You know where it shows how much time/power is left in the laptop....just curious I'm not sure if this is with every laptop or yours, just curious. If it is, I think if you right-click on it and hit power options it will come up with what power 'plan' your computer is using, whether it be performance, power-saver or balanced. This is what my laptop has, not sure if it does for you. As this sounds like a power-issue, I just wanted you to check if you have that and see if you can change your current power plan from whatever it is to something else; if it's performance, put it on power-saver and vice-versa. My dad's laptop had weird issues, not entirely like this, when the power-plan was set to performance and I tried to run Dawn of War: Soulstorm. Just wanted to see if this in any way might be something causing the issue, but probably not. Hope Demigod works out for you eventually!

Try running a good memory test program.  Demigod uses more memory than most games and could be exercising some flaky memory.  This would explain the non-deterministic nature of this issue.

K people I figured it out! for some reason my laptop thinks that it has run out of memory when I am playing Demigod and have my laptop plugged into an outlet. So, if I just unplug my laptop from the wall and play on battery, I can play Demigod as long as i want! I can even minimize it and plug in the laptop into the wall to charge, so it only messes up when it is displaying Demigod and charging at the same time, wierd huh?