The function RemoveMG does not exist in maps/mp/gametypes/_weapons.gsc. And that is why the mod doesn't work.
You can do now two things:
Comment the line 'thread maps\mp\gametypes\_weapons::RemoveMG();' in zom.gsc by adding // in front of it.
Or you can find the function and add it or make the function.
The function that you are probably missing is this. But it is moved to _weapons and renamed to RemoveMG.
PHP Code:
Remove_Map_Entity()
{
if(getCvar("scr_allow_turret") == "")
setCvar("scr_allow_turret", "1");
level.allow_turret = getCvarInt("scr_allow_turret");
if (!level.allow_turret)
{
deletePlacedEntity("misc_turret");
deletePlacedEntity("misc_mg42");
}
}
deletePlacedEntity(entity)
{
entities = getentarray(entity, "classname");
for(i = 0; i < entities.size; i++)
entities[i] delete();
}