Lots of fun, almost perfect.

Caution! Do not try the free version unless you are willing to pay for the full game. It is HIGHLY ADDICTIVE and the demo puzzles will leave you hungry for the real deal.

My only criticism is that the puzzle designer lacks a (perspicuous) way to "try" your creation before sharing it with the world. I have uploaded several puzzles, only to find that they were much simpler than they should have been because I forgot to lock something down.

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