Thanks for playing the game!
Regarding the points you listed:
- I'm not sure whether that's a good or bad thing? I have no issues on my end.
- The "lethal section" begins once night falls, wherever you are, and is part of the gameplay loop as a whole, so I'm afraid we won't be adding any checkpoints.
- The pick-up key also serves to interact and trigger voicelines anytime, so it's necessary that it is a separate key from throwing chestnuts. By the way, you can pick the chestnuts back up.