Help with Phish jam - Twist 2013-11-01

Hi all, I am a novice player working on improv. I am very new to chord progressions, scales, and related theory.

I am trying to figure out what is likely a simple chord progression for a Phish jam from 2013-11-01 around the 12:00 minute mark:

Here is the tab that i started.

Any comments/edits would be great! And any tips on what Page (piano player) is doing would also be welcome!