Sorry for the lack of updates. As expected, I'm using all my free time to play iDOLM@STER 2.
I received this at the same I received the game, so I almost had forgotten that I bought it.
Kara no Kyoukai Ongaku Shu (music collection) is the first commercially available cd containing the BGM of the Kara no Kyoukai movies. The tracks were already available in the cd included in the limited edition dvd's but this is the first time sold as a stand alone.
It contains 2 discs, with a total of 18 tracks. It seems like way too few to contain all the movies, and the reason is that most of them are a medley of all the music for each movie and are around 10-15 minutes long each one.