Audio problem: In the ballroom sketch when Janice is talking to Zoot, her mouth starts moving before we hear her even say anything.
Visible crew/equipment: When the group of pigs, chickens and frogs are singing "Temptation," the head of Dave Goolez (the guy who does Gonzo) is visible under the second chicken on the right several times during the sketch.
Waldorf: Well, you gotta give them credit.
Statler: Why's that?
Waldorf: Well, they're gonna keep on doing it till they get it right.