There have been bugs (still unresolved) about restoring purchases, in each case, the users have written to me, and I've immediately provided them coupons or a workaround.

Regarding stability, there sadly are some crashes on ios which I haven't managed to figure out at all. I'm planning a big move next week where I bump the version of libgit2, since I'm lagging behind by almost 1.5 years now, and I want to make it a regular occurrence. I'm hoping that will help with the stability.