God, the original prt.Mimi sucks ass.
No matter what you do, you're going to get some misaligned textures, in fact even the original Cave Story had some; I guess Pixel just didn't care. Also, the tile set itself looks bad, overall.
He definitely learnt from his mistakes, though, since prt.Cent and prt.Jail are so, so much better.
https://doukutsuclub.knack.com/database#search-database/
Gun seems really interesting based on the updates. Looking forward to it!