The developer of this game refuses to officially support mods (yet for some reason supports custom songs which are literally renamed .ogg files) , there is however a rather large modding community with a wide selection of mods, resulting in the mods breaking after updates.

Therefore there are programs to prevent the updating of the game. Unfortunately the method retrieving the game files through Steam requires you to enter your Steam login credentials into a third party app, this is obviously not at all ideal, but to limit legal issues of hosting the files for the game elsewhere, it has to be done this way.

https://github.com/Zagrios/bs-manager

Download version 1.27.0 from 2022

You need at a bare minimum Mapping Extensions, maybe Noodle Extensions and Chroma