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more /root/Features/Support for other keys in Key Events.thread
LateralGM doesn't seem to support keys like !@#$%^&*()_-+={[}]|\:;"'<,>.?~` in Key Events (note that all Numpad keys do work). I don't see why it couldn't support these keys, and it's just a bother that they don't work.
Game Maker does not support these keys.
Perhaps you should consider not being so close up and sung with Game Maker.