I was there with 2 friends and Steve you are right- the opener was J.F. Murphy and Salt. The south student center at Nassau Community College could only hold a few hundred people so the show was really intimate. We had The Yes Album and were major fans when this opportunity came along to see them. Fragile hadn't hit the stores yet and came out a few days or weeks later. I remember being surprised when they came out without Tony Kaye but instead with what seemed to be a girl keyboard player with long blond hair. It was Rick Wakeman and I quickly realized it was a guy. We were blown away by the performance and permanently changed. Two months later we were at The Ritz Theater in New York to see them again.
I attended this concert way back then with bated breath. I had been listening to YES on the local radio station 92.7 "WLIR" for some time and fell in love with the YES sound. The openning band was not Humble Pie but a local Queens, NY group which if my memory is correct was called J.P. Murphy & Salt. It opened with a guy playing bagpipes walking down the aisle to the stage, well what can be considered a stage for the small, one level south student center. We sat in the fourth row almost center stage between Rick Wakeman and Jon Anderson. YES took the stage and played the whole "YES" and "Fragile" albums. The concert was AWESOME and to this day I still love YES. I've seen them on the "Open Your Eyes" tour and a few other times when they toured through New York.