SECURITY guards had a hard time trying to hold back a wildly enthusiastic audience at the first anniversary celebrations of Commercial Radio II's programme, Ultimate Discovery. The stage was set up in the centre of the Park Lane shopping plaza and abutted on part of the road outside. The audience was able to watch the show from all four sides of the stage. The hot stars who performed were Andy Hui Chi-on, Vivian Chow Wai-man, Eric Suen Yiu-wai, Winnie Lau Siu-wai and Raymond Cho Wing-lim. The event also marked the extension of the programme's broadcasting from weekdays to Saturday as well. The fans were thrilled with the songs and dances, but their enthusiasm ran even higher when the singers offered to answer questions from the audience. Someone asked Winnie Lau Siu-wai why she had cut her hair so short. The singer said she wanted a new image, and besides, short hair has become the rage in Hong Kong. The singer's hit numbers for the concert included Change! Change! (Love Revolution ), with nimble dancing to accompany the songs. A very young member of the audience asked Andy Hui a question that took the star somewhat by surprise: ''Do you think you are good-looking?'' A slightly embarrassed but amused Hui said: ''I didn't expect a question like that from a little boy! I think I'm okay, but not good-looking!'' Andy sang two old songs, Never Loved Like This Before and With You in My Heart , as well as his latest hit, Wanna Say . The Saturday broadcast of Ultimate Discovery is from 10 am to 4 pm.