A recent weekend screening of “The Children Act” at the Kiggins Theatre in downtown Vancouver drew a small audience that was thinly scattered around the mostly empty, 340-seat auditorium. “The Children Act” is a serious, grown-up, issue-oriented drama about disease and faith. Hardly anybody came to see it on a Saturday night. Ten days later, Kiggins programming director Richard Beer posted a statement that acknowledged empty seats and announced a change in the theater’s mission.