Alan Ayckbourn, the great British playwright who has been long underestimated on this side of the Atlantic, finally caught a break on Broadway with a superb revival of his 1974 trilogy of interwoven plays, each set in a different room of a country house on a disastrous family weekend. The laughs are abundant; the stage gimmickry a hoot. But it's the hint of pathos behind the tomfoolery that makes it a resonant work of art. An Ayckbourn bonus treat: the U.S. premiere (just opened off-Broadway) of his newest play, the modest but winning My Wonderful Day.