Loving the map! I'm experiencing a minor glitch. When sprinting and sometimes walking on any of the stairs I could get some alterations in speed. This get's me hit by zombies every now and then. I noticed that you bounce up\down the stairs. I don't know too much about mapping but maybe I could help. If you haven't already, perhaps using clip textures on another brush placed in the stairs(covering the open spaces between steps and basically forming a ramp instead of steps) may help the player keep a consistent speed?