Hmmm.... It's very difficult to help without more information. I'm afraid "it just doesn't work" is not the same as "it runs but the screen is black", so you need to be a little more precise... Have you tried using the GM debugger and adding a breakpoint at the very start of the game then stepping through the code to see what's actually happening? This can often tell you where the issue is (for example, if there's an infinite loop that is preventing the game from running). Really, it would be a big help if you could give us as much information as possible, like what kind of game it is, how it's structured, what objects you have, what platform you're running on and targeting, what version and runtime are you using, etc... The more information you can give the more help we can give!