@Taylor:
10/10
(offtopic: That "Wind Fortress" song is no longer unused in Cave Story+ {ie, the commercial Steam version}, as there's now a mode called "Wind Fortress" that uses that song. You can hear it in both "Cave Story 3D"-styled AND the original one! {There's no "Wiiware version"-equivalent} ).
Also, that doesn't exclude mods, right?
Wind Fortress is song #25 in
Hope of Shané. (At least, one of the Beta versions of the song.)