When Clifford Odets wrote “The Country Girl” in 1950, it came after he had had a long career on Broadway and a second career in Hollywood. In both places he picked up enough information to write an encyclopedia on showbiz frustration. Instead he wrote “The Country Girl,” currently at the American Century Theater, about a washed-up Broadway actor, Frank Elgin (Brian Crane). It begins during auditions for a new play where the director, Bernie Dodd (Kevin O’Reilly) is trying to convince a producer, Phil Cook (Steve Lebens), and the playwright, Paul Unger (Christopher C. Holbert) to let Elgin read for the part.