Ok consider this.
ive got a cisco switch hanging off the monowall DMZ port
on that cisco switch is a subnet of 25-50 computers within same /24 class c

-if one of those computers is talking to another, does traffic even go to 
the monowall or does the cisco switch handle it all

-if it does make it to the monowall, do firewall rules apply

-if not, how can i make it so?