The plot over the MPAA's controversial screener ban is thickening. The Los Angeles Film Critics Assn. says it will cancel its annual awards gala unless the Motion Picture Assn. of America drops its ban on sending DVDs of films to critics and Oscar voters. The critics group insists the ban, which the MPAA is touting as an anti-piracy measure, will make it "physically impossible" for its members to see every movie released by the end of the year let alone copy and sell them on eBay.