NVG589 & Netgear Router for DLNA

I just got Uverse internet and my RG is the Motorola NVG589. My old setup consisted of a Netgear R6300 router. The Netgear R6300 has built in DLNA, which I used to stream media files from my computer to my bluray player and a Sony media player. I want to still be able to use my R6300 to stream media to my bluray player. I know there are media server programs for Windows, but from my experience in the past, the R6300's built in DLNA works much better. Can anyone tell me what would be the best way to set this up with the NVG589? I see that the NVG589 has IP passthrough and I saw a post someone made outlining how to accomlish this will another router and the RG. However, when I tried it, it didn’t work, so I”m thinking maybe I missed something or didn’t quite understand after setting up both routers, how to connect them to each other (WAN to LAN of the NVG589?). I also see that the NVG589 has something called “cascading router” but I couldn’t figure out what they meant by “network address” (not IP address) on the configuration page. Any help to get this working would be great appreciated.