Sarah Ferguson attended the Cannes Film Festival on Thursday, May 23, and despite looking “dazzling,” the ex-royal “had a moment” while addressing an audience on stage. Fergie kept telling the gathered attendees to “be quiet” and “to stop” as she fumbled with her microphone and “made odd faces.” The presentation was to thank artist Simon de Pury, whose portrait of the late Queen Elizabeth II fetched some 405,000 pounds for charity. “Quiet!” she exclaimed. “Because the incredible person Simon de Pury has done an amazing job tonight, this is exceptional, and all I want to say to everyone in this…