SYDNEY — The new prexy of Oz’s Cinema Owners’ Assn. of Australia has vowed to fight for a change in the rules governing exhibitors and distributors.Neil Pentecost, CEO of U.S.-owned Reading Entertainment, claims that COAA members, who represent 100 sites, continue to face difficulties getting firstrun films because they are squeezed out by Hoyts and Village and their affils Greater Union and Birch Carroll Coyle. These big boys dominate the Oz exhib industry. COAA will ask consumer and competition watchdogs to change the code, which it claims isn’t working. Reading has faced massive opposition from the established players since it announced its intention to become a significant Oz exhibitor. It has opened just 11 sites with 81 screens since December 1996.