(so I don't forget lol)
Please note that this only covers the Linux install. If you want to learn more about Beatoraja or BMS in general I would highly suggest the English guide
https://github.com/wcko87/beatoraja-english-guide/
NOTE: Since it's Linux, some level of technical knowledge is required, I will only target Ubuntu based system, however I'm sure (and that is where the technical knowledge comes in handy) you can adapt the instructions to your targeted distribution.
Step 1: Download Beatoraja. DO NOT DOWNLOAD THE WINDOWS ONLY VERSION (beatoraja-x.x.x-jre-win64). Download the other two instead.
https://mocha-repository.info/download.php
For clearness I will call the folder BeatorajaInstall (However you can call it whatever you want).
In this folder should now be some folders, beatoraja.jar, beatoraja-config.bat and some other files.
sudo apt install openjdk-17-jdk liblwjgl-java
https://gluonhq.com/products/javafx/
File structure should now be
BeatorajaInstall/
├── java-sdk/
│ ├── legal/...
│ └── lib/...
├── beatoraja.jar
├── Other folders and files
The file is already prepped with the "Locale fix" (https://github.com/wcko87/beatoraja-english-guide/wiki#locale-fix) (however it worked for me even without it).
If you don't wish to use the fix, simply delete -Dfile.encoding="UTF-8" at the end of line 4.
You may need to switch what version of Java you are actively using with sudo update-alternatives --config java and select the openjdk-17.
Alternatively if you don't want to switch Java versions, use the command, copy the path to openjdk-17 and use that instead of java on line 14 to set the version.
After running the start.sh you should see the settings window. Setup your game same way as on Windows, add your BMS/PMS files, IR, ... and launch!