I apologize! There seems to be a soft lock in the jam version! I'll try to get a patch up soon. In the meanwhile, you can try to skip that part by going to the saves folder at appdata/locallow/valonad/gamename to see the save file. Change the target scene from "scene(n)crossexam" to "scene(n)success1" (or (n+1) i forgor which number it was).
Could you tell me where exactly the bug with the sprites happened?
Also thanks on the note for Marisa's nickname. I basically just assumed that she gave a nickname for him but never actually looked into it lol.