soo a friend of mine wants to startup an own dedi server with exile and ryans zombies & demons,

problem is the zombies doesn't want to spawn well actually there only spawn 1 zombie,

he is still working on the set up for the server thats why i ask it here. really want to help him but without the knowledge i cant help him either.

so is someone willing to give my friend some advise or help him out?

*english may be bad sorry for this*