Okay looks like the throw you back a level is not a bug, but a feature ( seemingly arbitrary). It is Really frustrating to troow it in near the end of the game, when the first 30 or so levels do not do it.
Put basic shapes into holes: Okay... that is for toddlers, let's see where it goes.
Put cut up shapes into holes: Okay, I see this can be challenging and fun.
Put shapes into holes along multiple surfaces, some of them cut up: Okay I like this, more of this.
Put shapes into holes, but the surfaces rotate: Um, okay... a bit too much, but manageable.
Now let's also move the holes along predefines lines: Okay screw this.
Seriously, what is it with puzzlegames nowdays that they must introduce a new mechanic after every 3 levels? If you can't come up with a good challenge with just your core mechanic, then you shouldn't make puzzles. Obtuse doesn't equal clever.
This is a great game. Nice puzzle mechanic and somehow the art is drawn in a way that just makes this really funny. Even dying the same stupid way 4 times in a row isnt frustrating because I'm just a dumb worm with a dumb look on my face XD
Oh also, while you are working on a better menu (I saw you mention that in a response); could you maybe make the sliders on the current menu a bit bigger? Or maybe that's a browser problem? But the in-game sliders are extremely thin, making the already sub-optimal list form menu that much more inconvenient.
I love the basic idea though, not enough alchemy themed games :)
Interesting game, but it looses my interest quite quickly. I think adding names to things would be a great improvement, a nice touch to the game. Give it a bit more personality and atmosphere.
 "There Is A Bomb"){kind=icon}
 "Temple of the Four Serpents"){kind=icon}
 "Solipskier"){kind=icon}
 "Tough Growth"){kind=icon}
 "GameToiletMobile#5 : Big Dig North Pole Edition"){kind=icon}
 "Keeper of the Grove 2"){kind=icon}
 "Scalak"){kind=icon}
 "Amorphous+"){kind=icon}
 "Idle Intelligence"){kind=icon}
 "Hat Wizard"){kind=icon}
 "Factory missions"){kind=icon}
 "Idle Mage Attack"){kind=icon}
 "Idle Power"){kind=icon}
 "Apple Worm"){kind=icon}
 "Swords & Potions"){kind=icon}
 "Alchemy Idle Clicker"){kind=icon}
I'm looking into this problem - thanks!