Improve the installer (Patreon)

I often receive reports that an error screen appears after installing DLC costumes. This is because the files are not placed in the "costumes" folder, and probably many people just run the installer without reading the instruction. so I'd like to improve the installer so that people don't have to read it.

However, it only shows the explanation at the beginning. If I make an installer that automatically copies files, it requires to use the OS system like registry and I'm sure you know this will cause many problems. It takes a little time and work, but I'd appreciate your cooperation.And also, please be sure to read the "readme.txt". This is an earnest request from us the software creators.