Also, after closing error (L+R+SEL+START) and playing again (as i said, it restores data before going to shop), if you go to shop and buy anything again, the same problem will occur.
And another thing: if you buy anything from store, and there's no space for it on your island, game will kinda softlock in "choose place" state. (not freeze, but softlock: you can interact, but can't exit choosing place state)
Btw i entered in storm instead of shop>exit and won! I didn't even repair anything during combat, storm was easier than i excepted)
I'm gonna try higher difficulty.