Thanks so much for the wonderful feedback! I'll try to respond.
The hitboxes on the saws/orbs/...things are tiny, this was mostly a last-minute decision to tone down the difficulty, and would definitely be changed in a future revision as you're quite right, it looks very odd!
I think the restart feature is an unintended bug, as you're supposed to just re-start the level from scratch with no animals rescued. But I like the idea of checkpointing the ones you have found, so I will try and integrate that on purpose.
The getting stuck in moving platforms bug is definitely unintentional and is a hangover of using the same colliison layer for walls and platforms, I'm also thinking they'd probably be better if they were consistent with the regular platforms and that you could jump up from beneath them rather than hit them.