As title says - biter nests can regenerate health if some mods are installed (idk which, can try to find if needed)
Damage done to nests by this mod is over-regenerated. As result - all spawners alive no matter how much they spawn biters.
It would awesome if your mod would remove health regenereation from biter spawners.
Or dirty way - just use internal variable on spawner to count to 60 and on reach - force kill it.
