I find the music mod interesting, even if there are some issues.
Since I don't use cyrillic, SE can't resolve cyrillic names of some files so music isn't played and contextual music doesn't work.
Also, If I may, by unpacking the zip file under SpaceEngine addons/
folder, better if under a sub-folder named let's say SEMusicMod
, Space Engine will load new songs and effects without messing with default folders under data/
And I'd be careful regarding distribution of copyrighted material without proper rights to do so.
For the rest of the scripts, check how the .pak system works in this manual page
, when you start using it for addons distribution, when applicable, it's amazing.