Hi,
During the weekend i tried to check for the cause of the problem.
I noticed that you have around 20 spawns. I enabled spawn debugging for all of them and started a solo game. Only 2-3 spawns were working (green), the rest were red.
The problem with all of them was the pivot, it should be on the bottom center. I corrected that for all spawns and fired a solo game again to check. This time all spawns were green, and i did notice now that the spawns really work.
I thought all good and uploaded it to the server, the problem was slightly improved but still existed. barely anything spawned.
In the first version we were flooded with zombies.
I think a possible cause is the spawn in the small room with TV. many spawn there, but can't get out, which gets me to believe that the problem is not with the spawns, but the zombies just can't get out. They get out at a very small rate, I will have to test that theory with the previous version, but as far as i remember, they had no problems coming out. Changed paths in that room perhaps?
Also, most spawns are on visible places, such as the roofs, which are visible to the player. when a player has a line of sight to a spawn, that particular spawn won't spawn anything.
Since the spawns for the previous version are pretty much identical, i don't think thats the problem. but for i think adding more spawns to this big map will make it much better, zombies will suprise us from many other places and less blocked spawns from line of sight.
Those are my suggestions..