I'm pretty sure level 30 is uniquely solvable. Have you found a valid solution other than the one below?
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If this is called "Klein" because of Klein bottles, I'll have to say that this isn't a Klein bottle. On a Klein bottle, only one of the sides would flip you.
This game takes place on a projective plane (ℝP²). Notably, the fundamental group only has two elements whereas the fundamental group of a Klein bottle is infinite.