That was a rollercoaster! So much clever stuff packed into such a small space and it felt great to figure out the final trick.
I'll put it below the fold, so as not to spoil anyone (wish itch had spoiler tags!!) but you could put yet one more slightly mean sting in the tail
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Not sure if this wholly avoids other solutions, but by removing one square in the wall of the room with lots of blocks in it, you'd maybe force the player to preserve one of the 14 blocks in that room to fill the gap in the wall
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