Ok. In one NDS game the emulator makes a fatal error "The rom image has crashed" (something like that, you probably know). The error hapens in a certain part in the game every time. It has happened to an other game too.
I read about that ndstool in the stickied topic, but when I download it, it's just an exe that closes when I open it. How do I use that thing if that's the solution to my problem.
Also, one emulator didn't make an error at that certain spot in the game, but the game itself was almost unplayable on that emu.