how easily can you send saves? i can try and replicate the UI bug since i sort-of know how i did it, i can retrace my steps
off the top of my head, the way i triggered it was to die on the first fight of that level with 1 enemy (giant sloth thing?) left alive. the end-screen plays, and you'll be returned to the menu. loading would send you to that position. the message-box UI would start opening up, but stop abruptly since you're in a fight-tile (or node, whatever term) instead of the first tile of the level. in general, i'd advise redoing the way you get teleported to tiles on loading saves. often times you'd get weird outcomes, such as your path (from the start tile to your current map position) not being highlighted. i think it might be the case that your level begins with the player on the start tile, but then you would get teleported to the saved position. it might be the case of "my machine is fast enough for this to happen", or something like that.
also, excellent job on addressing all these issues in such a short time! keep up the great work.