I beat it after all. Save1 is before final boss (can't seem to be able to return to town), save3 is unlocked gallery. Or at least it says it unlocked it, since I can see locked tiles in gallery.
Also, not a crasher, but kinda soft-lock - if you pick second option from the diary submenu, you're forced to reset the game as it simply repeatedly prints errors.
Oops: that's not only the same bug, but it's a well known one, even if the author didn't figure out a proper fix yet - this is why the game is shipped with a System.sav file.