I appreciate you trying the game. Unfortunately I don't have the equipment nor time to address all potential problems for all platforms, so my focus is gonna be on Windows only.
As for web version, we can actually reuse the save, but it is a bit complicated. This is an location on Windows:
itch save location (Firefox):
C:\Users\[user account name]\AppData\Roaming\Macromedia\Flash Player\#SharedObjects\[RANDOM
LETTERS]\commondatastorage.googleapis.com\itchio\upload2\game\[RANDOM LETTERS]
We have to copy and paste the save into new version's folder in order to reuse it. I think this is too complicated for most players so I don't broadly advertise it. But it is possible.