Thanks everyone for the comments so far.
More information on some rooms:
Level 1:
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×L1 2W - It's okay that you only need one of the two roaches. And by design you're only supposed to have to wake one of the eyes.
Level 2:
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×L2 1S - It's possible to sink all the wubbas, but by design there's an easier solution.
L2 2S - There's not supposed to be any special trick to this room. It's just supposed to be confusing.
L2 1S1W - Too difficult for this early level? And it's possible this exact same room has been made before.
Level 3:
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×I spent almost 20 minutes building this awesome level, so I hope everyone appreciates my efforts!

Level 4:
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×L4 1S - You can do a little too much damage before the first spawn, so I'll probably tweak this room a little.
L4 1N2E - This room is much easier than it was supposed to be, and it may be practically unfixable. Not sure what I'll do about it.
Level 5:
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×L5 1N - There are shortcuts, but as long as you have to use the arrows in the middle at least once, that's okay.
L5 2N1E - Too difficult/random?
L5 3N1E - Too difficult?
L5 1N2W - I suspect players may find this too random, but there is a strategy: you're supposed to exploit the one place where there are obstacles on 3 consecutive diagonals.
L5 2S1E - There's an easy way to solve this, by doing some things after you've stepped onto the arrow. (That wasn't really the original plan, but it's okay.)
L5 3N - It's intentional that some of the tunnels work.
Level 7:
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×Level 7:L7 1W - You don't need to use all the mirrors. Any solution that doesn't involve keeping the tarstuff blob divided using babies and/or mirrors in unintended.
L7 1S - You don't need to use both the trapdoor paths. Any solution that doesn't exploit the fact that blue babies are created preferentially over green is unintended.
Other levels:
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×I swear I didn't copy off of Sillyman and Hartleyhair's Arcade Al Dente hold, which has an almost identical implementation to what I used in one room. I had already built mine before I saw theirs.