So, this was quite an interesting development that has gone by unnoticed?
Back when this game was released, Konami also released a 2-disc OST CD with an extra disc of radio drama contents. The track list was released earlier, and at a glance, we knew that the 38 tracks covered were obviously an incomplete representation of all the tunes in the game, especially since they do not even have tracks the ending theme(s).
http://vgmdb.net/album/30163But it looks like they released a digital version of the same OST via iTunes' Japan store on the same day, with all the on-disc tracks (minus the radio drama as well as the game-sized version of The Giving Tree) with a whopping additional 39 tracks, which actually make up the complete OST all the way to the 108 Stars' ending and Credits themes.
http://vgmdb.net/album/31907The full version of the Giving Tree is also available on iTunes separately, apparently.
http://vgmdb.net/album/31908Any idea if they'll release these later as a complete CD release? Or is iTunes-exclusive the in-thing in Japan nowadays? Exciting.