I'm really sorry about this - in general the saves should be compatible, but I don't know how to make itch.io keep them between versions :( I'll look in to it.
I think the saved positions in the browser are tied to the name of the game.
If there is also a version in the binding, the saved positions are not bound due to the fact that according to the name it is something else. (sorry for my english, i use google translator)