Recently anointed American Cultural Ambassador to the World by Congress, Alvin Ailey's venerable institution celebrates half a century with a world tour and dozens of works in tow. Opening night finds the company sharing the stage with Sweet Honey in the Rock, performing live their score for Hope Boykin's new Go In Grace; representing the company's history and namesake, Thursday's program features excerpts from 13 of Ailey's dances dating back to 1958. Other performances feature Mauro Bigonzetti's flashy full-company piece, Festa Barocca, George Faison's crowd-pleaser Suite Otis, and all close with Ailey's 1960 Revelations, whose reputation would seem impossible to live up to unless, of course, you've seen it.