Yeah for some reason that picture doesn't work. There's some issue of it being the wrong kind of png or something, apparently being uppercase PNG instead of lowercase is bad, in the case of rpgmaker. And I realised something was wrong about 3 minutes before the contest deadline so I didn't have the time to figure out how to fix it properly. And I can't upload/edit things now.
But you can just copy and rename one of the other pictures to skip that error message. I think I detailed how to in more detail in the installation instructions, including suggesting a pic of the same character, in a different folder, that isn't broken.
Thanks so much for trying out my game! :D
Sorry about the bugs.