There are 2 possible fixes! You can try:
- Changing your display's refresh rate (both increasing it and decreasing it work depending on your machine... The logic behind why is beyond me!)
- Pressing F1 in game. This should fix it, but it will also unlock the mouse from the game window. Not really an issue if you're playing in fullscreen on a single screen setup, though it might make certain sequences where the cyrsor is meant to be locked in a certain spot act a bit weird, but still playable.
Hope that helps...! These are temporary fixes, this is a Game Maker issue and I've no choice but to wait for the engine to receive a definitive fix.