According to my research, the original music is "The Last Hero" (https://demozoo.org/music/297439/) by Future Freak / Dexion for the Commodore 64 from 1988. It's also known as "Arcane Theme" (https://demozoo.org/music/155207/) by Zetrix / Arcane for the Commodore Amiga, which was created in Future Composer. The internal mod-tracker text of Estrayk's version states he converted the Future Composer version to Pro Tracker, which would be the one by Zetrix / Arcane.