Is there a way to compose one's own BGM? I've always wondered. If so, can is there a tutorial or key for stuff like that?

MML. Type in MML and bring up the help menu.

Litterbox(made by glennxserge) can be used to make music without knowing MML. KEY:2323C28E This is a unofficial version of litterbox that i've made to fix some bugs.

Is there a way to load my MML into my game? I tried this:

When you export an MML you can copy paste de content on your code or load the file. The latter can be done with this code: SONG$=LOAD("TXT:ENDLESSWAR.MML",0) BGMSET 128,SONG$ BGMPLAY 128