Always nice to see a PICO game pop up, and this was a lovely implementation of the theme within the confines of that ecosystem.
I don't personally play too many puzzle games, so I'm not sure how to describe it; perhaps it's Sokoban-esque? Regardless, this worked really well, both in implementation, use of the theme, and the actual feel in the game. There was definitely a knack to these puzzles and when I started encountering ones I had seen before the penny started to drop.
There were certainly some I just could not solve. I'm not sure if there's a situation where if I made a bad choice for the first move, all the blocks ended up in terrible positions that were hard to recover from, and whether this is a 'me' issue (which is pretty likely as I'm quite poor at these games).
I don't think I have much to say critically; I really think everything was designed well. The tutorial was helpful, and I love the overall look and feel of the game. Perhaps a little more variety to the puzzles could have been great, but honestly it's a charming and fun little PICO game that doesn't need much more! Many thanks.