I can't find specific instructions to port forward a wrk54g. But I did come across this: "The WRK54G is stripped-down version of the LinksysWrt54g wireless router" http://www.seattlewireless.net/index.cgi/WRK54G

I also came across these articles: 1. Article 1 2. Article 2 & 3. Article 3 If you forward a port, yu will need to establish a static IP which is included in the instructions below. Use [B]Port number 6346]

I can only guess that the port forwarding (opening a port) technique is identical to WRT 54G: (A) Port Forwarding instructions for the Linksys WRT54G or else (B) Port Forwarding instructions for the Linksys WRT54G v1.1, v2 & CA

You will also need to adjust the settings within LW: Force IP instructions & sample image for LW

See how you go.