I cannot get this game to run. It used to run fine but now the PLAY button in Galaxy goes grey for about 3 seconds and then turns green again. I tried changing the compatability settings and adding DEP for the exe.

Anyone else find a sulution?

I'm running Windows 8.1

Sorry if this seems unclear...

This is probably too late for you, but for the benefit of future players, this sounds a lot like missing DirectX files.

The simplest way to troubleshoot is by going to the installation folder and manually clicking the game executable file to open it, you should get an error popup. If it mentions anything about missing DirectX files google "DirectX runtime" and make sure you get it directly from Microsoft -it's free so there's no reason to get it from some sketchy website. Install it and (optionally) right click the executable to apply compatibility settings and it should work now.

Sorry for the late reply - your solution worked so thank you much for the help!