Just extract the contents of the archive in the game's root folder, overwriting the "MP3" folder.
Backups are included in the "MP3 - music backup" folder.
Replaces the main menu, adventure map ambiance and combat music with classical music pieces. Town and campaign music is untouched! I've made this for myself and it's really a matter of taste. If it's not for you, then tough tiddies. If it is, then glad to hear it. As far as I know, none of the music used isn't copywrited, but in case it is, all rights go to people that have deceased more than 100 years ago. Not looking to update or change it so what you see is what you get.