MiniDLNA for WNDR3700v2 running DD-WRT
Simple guides for doing this.. Stock firmware comes with DLNA build in, but this feature is missing from DD-WRT by default.
Basic guide to install Optware on the device (allowing you to install whatever packages you like form OpenWRT) Here
Package that worked nice with my DNS-323, working inotify, etc Here
Basic Config guide for MiniDLNA Here