The national tour production of Oz that came through here last year handled it pretty simply. The "Kansas" scenes were almost entire lit with low-angle sidelight from dance towers in each entrance - a shin, mid, and head all in a warm straw color. It was really effective at enhancing the differences between Kansas and Oz, but it also did a great job at hiding makeup imperfections. The Head Electrician just told us not to include the three male principals during the last scene, and it went over fine. I'm sure they had wardrobe offstage rubbing the makeup off as fast as possible, but because of the lighting choices, it wasn't a huge deal if they didn't finish, and they didn't really need to apply new makeup anyway.