So now we have the full composer credits from Square Enix's official announcement:
Masashi Hamauzu (Monomusik) / Shingo Kataoka, Hayata Takeda, Takashi Honda (TOSE) / Ryo Yamazaki (Square Enix) / Ryo Shirasawa (noisycroak)
http://www.square-enix.co.jp/music/sem/page/woff/