CivNet and Civ 2 MP Through a DHCP Router

[ctbeal]

I have been playing CivNet for years, and just bought my copy of Civ2 MP recently. I am playing on a Linksys router connecting our LAN and cable modem. Unfortunately, I cannot seem to connect to games on the internet on any machines on the LAN. Also, I cannot host games as my machine cannot be seen through the firewall/router as it has a 192.168.x.x IP address issued by the DHCP from the router. Short of purchasing a separate IP address from the cable company, how can I play and host CivNet and Civ2MP games through my Linksys router?
Thanks.