use the ip address of the duo and the http port that you have set up for it and the ftp username and pass... basically mine looks like this

host or ip address - *******.dyndns.org
Label - Vu+ Duo
Zap Mode - multi tuner
Quality - upto you
Web-Interface Port - 1222
Streaming Port - 8001
username - root
password - (whatever your ftp pass is)
and leave the rest default

that should do it