There's no instructions and I'll be honest. It's entirely because this is my first foray into itch and I didn't realize it'd handle save files differently. I plan to look into a way to sort of export save files for use between versions. I apologize.
No problem, I seem to have hit the end of content for the current version as well.
Another thing I'd like to see is the ability to set the game to "medal hunt", unlocked after beating stage 50, it automatically locks your stage to the creatures you don't have a gold medal of yet. If it doesn't look too troublesome to implement.
That's an interesting idea, could be some good QoL. I don't know when I'd be able to get around to it, but I'll note it down. In the meantime, theres a way to lock your Stage in the Settings so that you can farm specific enemies. Your idea would be a lot more hands-off overall and more suitable to an idle game, I agree.