^Probably hasn't positioned the layers, then... click on any layer button in the top right, and then click on one of the arrows or the dot in the bottom.
Anyway, copypasta tip time!
CajNatalie wrote:Always put player start position far away from any collision horizons above... that means that in a narrow stage put the start as low as possible, because SoRR will start player 2 a good distance above player 1.
For really narrow stages, put some kind of opening in the collision map for player 2 to escape through... if there's no area that should be walkable at all above the start position, you could try using a block of yellow and putting player 1's start there, then testing and see if you can drop out and escape.
Make sure the escapable zone is moderately large. Overdoing it and having funny collision is better than underdoing it and leaving a game-breaker in.

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