Very cute and engaging puzzle idea!
It would be nice to be able to preview the robot's movement from a certain tile or piece. For a few of the puzzles, having to wait for the entire process to play out could get tedious even with the speed modifier, as I wanted to get past the parts I already knew were successful, but needed to slow it back down to see if the new pieces I'd placed would work. I'd need to think a bit about how to balance that idea to not completely negate the idea of it auto-playing.
Regardless, that is a very minor criticism and was only relevant on a few of the puzzles. The character design is very cute and I liked the pixel art mountain landscape. Well done!
Viewing post in Knuth's Climb jam comments
I considered showing the robot's path, however I think that would make it a bit too easy - and rob the game of the fun of tracing the path across the levels yourself using the mouse. This remind me of the GMTK balatro video, how previewing the outcome can sometimes spoil the fun of a puzzle.
I also quite enjoy the "set up and then watch it go" structure to the game, rather than the idea of pressing a button to make the robot take its next move. Perhaps I could give the speed slider a greater maximum for this purpose, or something like that. This is a tricky problem to design around, as you mentioned.
Anyway thanks for the in-depth feedback, I do appreciate it!