Skidmore College’s Musical Theater-Opera Workshop, with the Musicians of Ma’alwyk, will perform parts one and two of the work-in-progress opera “Bell” by composer Richard Einhorn and librettist Kathryn Walat. The Saratogian reports it takes place at 7 p.m. Thursday, April 20, at the Arthur Zankel Music Center. The event is free and open to the public.