The booklet does NOT credit BGM solely to Toshimichi Isoe, or in fact anyone: this is a rare ZIZZ release without specifics. ZIZZ's page for the album gives credits for four of the BGM tracks, and three different ZIZZers were responsible for them, so this was surely a group effort like the other Nitroplus games.
田中久美子: Most likely read Kumiko Tanaka (a few hits on this name, mostly kind of dubious)
小熊佐絵子: Probably Saeko Oguma:
http://www.t-bunka.jp/onkon/04nyushousha/04_03.html
石川祐治: Maybe a mistake for Yuji Ishikawa (石川 祐支)?
http://www.venus.sannet.ne.jp/cellis...a/profile.html