Nice game. After completing this I looked at many of your other (puzzlescript) games and they all seem playworthy, but:
None of them have a save/continue feature. If you hadn't provided the link above to the version of Crusher on the puzzlescript site, which does have that feature, I wouldn't have completed Crusher. I play puzzle games in more or less short sessions of less than 20 minutes, and while that may cover 6-7 levels at the beginning of a game, it may be only 1 or 2 later. And I hate having to go through the earlier levels again, it is just a waste of time that I could spend actually solving new puzzles!
I'm not sure how hard it is to implement that feature, but since your games are level based a simple level number should be enough, and then an option in the title screen to restart the whole game.
Again, I liked Crusher and play "Cat chases Mouse" at the moment (which seems to be relatively short to not need a save feature at 6 levels) but for your other games that feature might be useful.