[kyubihanyou]

What a coincidence: I just wrote something relating to this in my reply to your other comment.

-On his MySpace page, Yousuke Yasui is specifically credited for this game as "Compose & Arrange" and "Arrange or Remix." Furthermore, the music he chose [via Youtube video] to represent his work on Transmission was VS. Zero, so that's a confirmation right there. I'd say that's the supposed "Remix," and I'd have to say that the "Compose & Arrange" was Garden System and/or Old Generation Area's stage themes.
[NOTE: I originally thought those three were Saso's and Yasui only did Threat Arises and Suspicious Events; all the others linked together by some part or another, then went to Shinji. That theory's blown.]

[Bold = Confirmed ; Italics = Implied]

Group 1: "Drums" - In the Room, Internet Densen Area, Water Service Bureau, Game Center, Demolished WWW Area, Legendary WWW Area, Undernet, Hero, VS Life Virus R
Group 2: "Downward hum" - Electric City, Zero Account, Epilogue
Group 3: "Main Theme Power" - Theme of Megaman Network Transmission, Stage Clear, Eyecatch, Game Over
Group 4: "Dark tone & piano" - Suspicious Event, Threat Arises
Group 5: "Background piano": Electric City, Game Center, Zero Gravity Area, Game Over
Group 6: "Sound too similar 1 [similar melody]" - Firewall Battle, Staff Roll
Group 7: "Guitar" - Blazing Internet, Power Plant, Abnormal Gravity Area, Navi Battle, Firewall Battle
Group 8: "Very High-pitched synthesizer": Garden System, Power Plant, Old Generation Area, VS. Zero
Group 9: Stretched synthesizer note [low] - Bank System, Zero Account, Unknown
Group 10: "Twinkling" - Relaxation, Bank System, Zero Gravity Area, Epilogue, Game Over
Group 11: "Jazzy" - Relaxation, Blazing Internet, Power Plant, Navi Battle
Group 12: "Slot machine" - Electric City, Legendary WWW Area, Hero, Epilogue
Group 13: "Sound similar 2 [similar part]" - Internet Densen Area, Electric City
Group 14: "Stretch synthesizer note [high]" - Relaxation, Epilogue
Group 15: "Sound similar 3 [similar sound]" - Theme of MegaMan Network Transmission, Blazing Internet

-Kaze wo Tsukinukete was originally composed by Yo Tsuji and arranged by Akio Kondou, so you can drop it from the list. Besides, Arika's two implementations of it made the original look like ____ in comparison; I don't see how it wasn't also used for "Theme of Megaman Network Transmission", as the other games link the title, credits, hero, and depression themes.