Sinclair Broadcast, whose stock price has been battered over its plans to broadcast a documentary critical of Senator John Kerry, gained back some ground on Wall Street yesterday after it appeared to reduce how much of the film it would show. The company's critics, which have included institutional investors, consumer groups and representatives of Mr. Kerry's campaign, were not mollified. At the same time, the producer of the film, "Stolen Honor: Wounds That Don't Heal," which presents former prisoners of war denouncing Mr. Kerry's statements against the Vietnam War, said he was disappointed that the film might not be seen...