This should help: http://wiki.modsrepository.com/index.php?title=Call_of_Duty_bo3:_ZM_Models

I found this in the _zm.gsc

function get_zombie_count_for_round( n_round, n_player_count )
{
	max = level.zombie_vars["zombie_max_ai"];

	multiplier = n_round / 5;
	if( multiplier < 1 )
	{
		multiplier = 1;
	}

	// After round 10, exponentially have more AI attack the player
	if( n_round >= 10 )
	{
		multiplier *= n_round * 0.15;
	}

	if( n_player_count == 1 )
	{
		max += int( ( 0.5 * level.zombie_vars["zombie_ai_per_player"] ) * multiplier ); 
	}
	else
	{
		max += int( ( ( n_player_count - 1 ) * level.zombie_vars["zombie_ai_per_player"] ) * multiplier ); 
	}

	if( !isDefined( level.max_zombie_func ) )
	{
		level.max_zombie_func = &zombie_utility::default_max_zombie_func;
	}

	n_zombie_count = [[ level.max_zombie_func ]]( max, n_round );
 
	return n_zombie_count;
}

Could this possibly be modified to cap the amount of zombies there are per round?

Doesn't that just change the maximum amount of zombies that can be alive at one time? I'm looking for something that will only spawn 24 zombies per round.

Is there a way I can change the amount of zombies that spawn per round? My map is pretty small and I would like the classic amount of zombies per round from World at War.

Go into the weapon file and search "tracer." That's the bullet trails. I'm pretty we only have access to smg trails at the moment, so just type "smg" for the tracer type, "smg_enemy" for enemy tracer type, and "smg_uw" for underwater tracer type.

This might be a dumb question to ask, but have you ticked the "ADS" option in the weapon file?

Good news, I figured out what I was doing wrong, and it fixed my problem. It turns out that zombies do spawn in zones that are adjacent to you; I was just scripting the zones incorrectly. Basically, I never scripted zones 1 and 2 as being adjacent to each other, so if I was in one zone, zombies wouldn't spawn in the other.

So, I have a door sound that I would like to be played when a player opens a door in my map. The problem is that I can't seem to figure out how to get it to play. I have set up the sound alias and the file is set up as a wav at 48000 Hz, and I've tried using all the sound script_structs in radiant and attaching it to the trigger for the door, but it doesn't play when I open up the door. Anyone know how to do this?

That may be the case but we don't know if they might have just used 1 zone for the entire bottom floor which is what they probably did since its a tiny map.

Just went and noclipped into the help room on nacht, and I didn't die, so it is all one zone. Does this mean the spawners in the help room were set up to the triggers for the door and debris?

This is how it always has worked. I believe you can overlap zones but i'm not too sure. once you are in a zone, zombies will only spawn in that zone. In co-op, zombies spawn in any zone a player is in, which means more than 1 zone spawns zombies.

This is the best way for things to happen, as it allows zombies to spawn near you, and not across the map. I don't know about you, but one of the things I hate the most is when i finish a wave, but 1 or 2 walkers I cannot seem to find, and it takes me minutes just looking around to find it.

If you really want to, I believe you can hook up zombie spawns to a trigger, on one of your doors/debris, and that will cause them to spawn no matter where you are in the map. At least it was possible back in WaW.

Is this really how it's always been done? For example, if I'm playing Nacht in WAW, and I'm standing in the "help room" with all doors open, zombies will come from the spawn room and the upstairs rooms. I'll try some of the ways you mentioned to see if they work.

I don't think so. I've played custom maps where zombies are spawning in multiple zones.

Have you included the sound aliases in the notetracks of the animations?

The problem I'm having is that zombies will only spawn in the zone I'm currently in even if all other zones are open. For example, if I'm standing in zone 2, only zombies will spawn in zone 2, and they won't spawn in the start zone or any other zone.

Use the "Tom xAnim Extractor" from this page: http://tom-crowley.co.uk/downloads/

Is there a way to change the sounds that the zombies make? Are there sound aliases that are used for these sounds?