I assume it's a similar process to add a specific music too? I also saw that there's a specific object that is supposed to change music in certain situation if you link it to a trigger.
yes it's the little monitor looking thing called 'setbgm' you need to set the music's name with the console command NAME e.g: NAME nature and you need to set up a trigger to activate it (let me know if you nee help with that)