Installing this now, and I anticipate I'm going to love it. Two of my favorite games, Europa Universalis II and the original Hearts of Iron, used genuine compositions, and I can't express how much it added to the playing experience. The feeling of beating back the German invasion of the USSR with the 1812 Overture playing in the background is incredible.
So, major kudos to you for doing this.
I know it isn't possible, but I wish you could set some music files to play during a certain time period, and others to play at other times. That way, for the first 50 or 60 years of the game you could have Baroque music, which would be appropriate for the time frame, and then for the rest of the campaign it would switch over to 18th-Century/Classical.