Portnoy, Tony Levin, Diego from Haken, and Eric from NMB did Paradigm Shift, Acid Rain, and Universal Mind.
Main band for the 12 Step Suite was Diego on keys, Eric on lead guitar, Connor from Haken on bass, and Rich and Charlie from Haken both on rhythm guitar (though they did jump in on a couple unisons). Ross was the primary vocalist, with Daniel Gildenlow DOI g the first 2/3 or so of This Dying Soul and Ted Leonard doing most of The Root of All Evil. Mike did most of Repentance. Ross, Daniel, and Ted all sang the very last vocal section of The Shattered Fortress. No additional DT material played.
Overall I can honestly say this was phenomenal. Considering the complexity of the material and the limited rehearsal time, they were fairly locked in. There was just one minor but noticeable slip up in Acid Rain that I could tell. Eric is an absolute monster, he nailed all the leads. I was a little worried about how Ross might hold up but he was mostly very good. Also, as Nick pointed out, he mostly struggled on parts that I wouldn't be surprised if James had trouble with.