BRIEFLY: Keith Lockhart, new conductor of the Boston Pops Orchestra, will lead "Liberation 95," the musical-multimedia commemoration of the 50th anniversary of the end of the Holocaust, Nov. 13 at the Dorothy Chandler Pavilion of the Music Center. The musical score for "Liberation 95" is being created by composer Meir Finkelstein. Among the participants will be actor Billy Crystal, television personalities Bob Saget and Martin Bookspan and members of the Los Angeles Philharmonic, L.A. Master Chorale and the Crossroads School Choir. . . . Running through Dec. 28, an exhibition titled "Kirsten Flagstad: Voice of the Century" opened recently at San Francisco Performing Arts Library & Museum. The exhibit includes photographs, recordings, costumes, and other items related to the five-decade career of the Norwegian soprano, whose centennial is being celebrated this year.