Thanks! Yeah I suppose I just like dove right in there... The first and most important part of copying a song is just to be able to hear it well... I use a program called NSFPlay that lets you mute tracks and slow them way down while preserving the quality, and it even shows a little keyboard with colored dots showing you where all the notes are.
I had actually made the Lisp previously because I had a specific need for it - I wanted a more slimmed down version of Clojure that was native to the browser for educational purposes. But when I heard about the game jam I suddenly got really excited at the thought of "testing" it to see if it could actually work! To be honest, I might not have even bothered otherwise.