TLer here.
The issue with the True End image is that the game events reference a normal ! while the actual file name has a different !.
I renamed the file in the game events on accident.
Renaming
\img\pictures\bセンキューフォープレイング!.png
to
\img\pictures\bセンキューフォープレイング!.png
is a quick fix.
Though you just get booted to main menu after the True End, and I can't remember if that was something I overwrote.