Here is a bug that frequently occurs. It was working fine, but after adding some more things it started happenning. It seems to happen more often in the exported game than in game mode (which is odd, because normally I've found bugs happen more in game mode than in the exe).
I have a physical response function that's being activated on a collision (where else ). It hase the velocity multiplier to 0, so there is no velocity at the end. When I collide with something, there is usually a slight angle. So if there is a horizontal wall, and I hit the bottom of it, with a slight angle to the right, x should increase by about 1 pixel, and y should increase by about 2 or so (so that I'm no longer colliding). But instead, x increases by way to much, and I go power-sliding along the wall It is fun though...
I'm not sure, but there might be some other occasional problems, but they are probably related.