If you are looking for how to use custom music in the game, an official update now supports this feature on PC. Key requirements for getting your tracks to work include:
The game is designed for music between 60 and 120 BPM , with 70–90 BPM being the recommended "sweet spot" for gameplay. BPM.BULLETS.PER.MINUTE.Custom.Music-DOGE.part1.rar
Use free software like Audacity to trim your tracks or adjust their tempo to fit the game's metronome. If you are looking for how to use