In my game, the ball bounces against the player-created yellow barriers that you see. For this I've used the Reverse Custom Movement event. The problem arises when the player creates two yellow lines in the same place, one on top of the other, at which point I presume the ball bounces against both lines simultaneously, and runs the Reverse Custom Movement event twice, therefore the ball doesn't change direction.
A related problem is with collision against the blue outer walls, which are made up of 32x32 tiles. Note the number on the ball. This decreases every time the ball bounces against a wall/yellow barrier, but sometimes, when bouncing against the outer walls the counter decreases by 2. I presume this is because the ball is bouncing at the point where two tiles meet, therefore bouncing against both and running the tile's collision event twice?
Any workarounds for this double collision would be appreciated. Thank you.