The midnight screening Cohen's film, "Borat: Cultural Learnings of America for Make Benefit Glorious Nation of Kazakhstan", had been getting raucous screams of laughter before the projector suddenly cut out 20 minutes into the film, turning merriment into dismay and prompting Cohen to do some quick improvising.
"I will apology on behalf of Kazakhstan for this little mistake," Cohen told the crowd in the voice of his alter ego, Borat Sagdiyev, the satirical Kazakh journalist who is the subject of the film.
Earlier on Thursday evening, a screening of "The Journals of Knud Rasmussen" officially opened the festival. That film, a look at Canada's frozen north and the cultural destruction wrought on native people by European Christians, drew praise as an inventive choice to start the festival.
But it was Cohen who stole the show, wringing every last laugh from the character he developed as part of his TV hit "Da Ali G Show". The comedian has ruffled more than a few feathers this year with Borat, a naive journalist he unleashes upon unsuspecting real-life subjects unprepared for the character's overt sexism and anti-Semitism.
Da Borat Show
Cohen, who is Jewish, was threatened with a lawsuit earlier this year by Kazakh officials upset with his portrayal of the country as a nation of drunks, racists and sexists
He arrived on the red carpet on Thursday on a wagon pulled by four women dressed as peasants. A donkey rode in the carriage with Cohen as the crowd chanted "Borat! Borat!".
"There were two more of them," he deadpanned, when asked about the women. "But they escaped in Bulgaria."
Cohen typically unleashes Borat's slurs and inappropriate remarks while interviewing unsuspecting subjects, with the punch line provided by the subject's reaction, which is often uncomfortable agreement. He has said the segments are "dramatic demonstration of how racism feeds on dumb conformity, as much as rabid bigotry".
The opening minutes of his film had the audience in stitches as Borat leaves his home town in Kazakhstan on a quest to learn about American life.
His early scenes in the United States have a slapstick hilarity to them as he accidentally lets a chicken out of his suitcase on a crowded New York subway and then walks up to men on the street to kiss them hello. In one scene, he mistakes a hotel elevator as his room, and startles the porter by beginning to unpack his belongings in the cramped space.
Moore and Charles took light-hearted questions from the audience before Cohen came back on stage. After about an hour of waiting, the audience was told the projector would not be fixed.