Please use turbo mode. (Shift + green flag or See inside > Edit > Turn on turbo mode) Don't enter and exit fullscreen or see inside while listening because it causes notes to go out of sync. You can use this link too: https://turbowarp.org/722525549?turbo Fullscreen is not reccommended. After a week of hard work , 11 spirtes, 86 scripts, 2000+ blocks, 17 lists and a lot of variables, I finally finished it! Sometimes notes can go out of sync but I am sure beats are right. I think this problem is about Scratch. There is nothing I can do. You can play again the part you want at the end of the project. This project was really hard to make, so if you enjoyed please leave a love and fave.
My entry for @Pinkmouse773's contest. 99.9% by me. 0.1% @griffpatch (I realised I can make an invisible box to let sprite go offscreen thanks to him)