If you figure a minimum of 16 square feet per person, which means that each dressing room can accommodate 12 actors. 12 actors times eight dressing rooms theoretically give us space for 96 actors. But legally we could if we wanted to. Two rest rooms at that end of the hall, each with a toilet and sink. At this end of the hall we have two rooms which were probably the doctor's offices, each with a private toilet and sink.
Nothing makes an actor feel loved as much as a hot shower.
We would need to put in a couple of hot water heaters for the showers. That gives us two toilets and showers for the men and the same for the women. Looks like the doctor's reception rooms. We could use one of them as the Green Room. That would mean running more plumbing.