Learning curve is a vertical cliff if you're not very familiar with both original puzzles but great game! :D
As someone that works with software development I understand that adding a tutorial might not be a priority over other suggestions (there a tons of good ideias brought up by people here!) and will take dev time. A quick and simple solution that I believe would address most people's needs in this case could be to put hints/tips/tutorials in the Description section of this page. It would save you a lot of time and would be quicker/simpler than implementing it in-game.
BTW: great game, clever idea, congrats! Took me a while to figure out how to play, but now I'm addicted to it =P
Last suggestion, for the (hopefully near) future: I'd love a mobile version.