Interesting concept, quite well implemented. Some tough puzzles. Bug: There are two levels called "Surrounded by flames". 2-6 and 3-11. After finishing the 2-6 one, 3-11 also shows up as completed, even though it is an entirely different level. And since 3-11 seems completed, now 3-12 and 3-13 are available to play even though I haven't yet played any level in chapter 3. Is it possible to allow controls to be configured? I really wish Z was for Undo. I don't really like the portal mazes, they're hard to...