Um engenheiro de software da Microsoft que trabalhou no Firewall do Windows forneceu uma resposta essencialmente à mesma pergunta:
Is anybody aware about Windows 2008 firewall limits like Max Number of Rules or Max Number of Remote Addresses?
E a resposta dele:
There is no limit to how many rules can be added(other than the cap of UINT64 for the filterId), nor how many conditions can be in each filter (other than the cap of a UINT32 for the numFilterConditions).