The booklet doesn't say what composer did what. There aren't even any liner notes, unfortunately. Just the album staff as transcribed in the notes.
Tracks 1, 6, 7, 10, 11, and 13~17 were composed by Junko Shiratsu per this album apparently:
http://vgmdb.net/album/3066. So you can rule those out as Naganuma's work.