Let's see, for FII I was at the
*Fix for 96 show - The Strand in Providence
*the WHJY birthday show at Lupo's (which featured the first ever performance of NM and Hollow Years, plus debut of the album version of Burning My Soul.)
*Boston '98 show with Big Wreck, which featured the Fasten Your Seatbelts version of Ytse Jam
*Great Woods, MA - ELP/Deep Purple tour
*Christmas show '98 at in Toad's Place CT (which featured most of the FII b-sides, including the first ever performance of Where Are You Now). Maybe my favorite show.
In terms of communicating feedback with the band, like many fans, I waited in the back of venues (often in the cold) and was lucky for the chance to chat with the band after each of the above shows. I recall talking in particular with MP about the album vs '96 version of Take Away My Pain, the lyrics to Raise the Knife (go figure!) and clarifying with JP the lyrics to the extra verse removed from Lines in the Sand, and other topics.
There was no expectation by the fans to hear the songs any way other than the album version, since the demo versions were very scarce, and only a few fans were exposed to them at the time, so the band played the versions the audience would expect to hear live (with the exception of the tweaks made to Take Away My Pain, as Scotty mentioned above).
To answer your other poll, I've always preferred FII over SFAM.