I am attempting to do a solo acoustic guitar arrangement of Flowing Destiny, from the soundtrack to the video game Zone of the Enders. Sort of like what lonlonjp does with Final Fantasy and Zelda. Yes, I know, I am a huge dork.

However, I am having trouble figuring out the chord progression to most of the song. I have the vocal melody figured out, but can't get the backing chords.

I would be hugely appreciative if somewhat would give me a hand with this.