Ive been playing early morning and zombies do not spawn if there is less than 20 people in the server. If they do spawn they wont spawn until after 4 mins. HUh huh!!!... Also the respawn after you die doesn't work either when there is less people in the server.
yeah there was that problem yesterday. Aceros came and used his magic to fix it. but between you and me, i think it started working on its own.