I think that is what is casuing lag becasue the zombies are spawning so fast after another dies. I like BB and all, but the only thing that needs to be changed is that the zombies don't spawn in the same places, i think it needs to be like svencoop {not entirly} i mean not entirerly like svencoop i mean by in svencoop there are a few monsters, u kill them and move on.... later few monsters, kill em too. This is what im thinking for BB instead of they respawning every second. But in some points their could be rush points like in svencoop that u have to ovetake the AI and keep rushing until you break through their spawns. I think this will greatly reduce the lag. Thanks

I think the lag problem isn't caused by fast respawning zombies, but by zombies spawned all over the map. Every "living" zombie generates a small amount of upload for the server, which is multiplied by the amount of players. You might have noticed that zombies only spawn when you are in the area, so if players just run through a part of the map, they'll generate zombies, but they don't destroy them. BB automatically slays zombies after some time of inactivity to reduce the drain on the server upload, but that often doesn't work fast enough, especially with lots of players. As soon as the server tries to upload more than he is capable, he won't be able to send all the necessary data to the clients. This results on the ping>2000 problem. You might have noticed that sometimes the zombies keep on marching like normal, and some of the players still fight while you're frozen in place and your ping goes for a new record. This is because the server sends data about the NPC movement and player movement to you, but is unable to verify the data (which requires upload he doesn't have) you send him (like moving or shooting) and thereby just drops it.
Please note that I'm guessing all of this, and that it is not based on accurate knowledge.

Also the weapons you drop,they wont dissapear

I think the netcode is casusing the lag oops! But i still like my idea about where their are a couple of zombies shoot them becasue respawning zombie is not realistic and don't even tell me that THIS MOD IS A FUN MOD NOTHING BIG!

@Nekrotzar: That describes it quite accurate
plus there is the overall ent and model count which also produces a lot of cpu work.

it sure does lag alot with all of that AI being active at once...

Dude making it like sven coop would suck.

The zombies everywhere is what makes this game fun, taking out the contant horde of them would make the game suck ass.

Please don't do what he said, PLEASE! It would ruin BB