Ok, I'm on an ipad in the airport so i will explain how it works.

all audio on the dms amps is streamed.  This is done so all zones stay in sync with each other.  Even the local inputs get streamed out onto the network. That is why if you dont plug the dms amp into a network, you will never get any audio out of it.

If you are controlling the dms amp via ir only, then it doesnt need to be connected to your main network.  You can use a simple network switch with only the dms amp connected to it.  You would plug your laptop into this switch to configure the dms amp.

if you want to make configuration much simpler, then use the mfs8 switch from urc.  This allows you to access the amp from the main network, while keeping all of the dms traffic off of the main network.  If you tried plugging the dms amp into the main network without the mfs8 switch, you would crash the network.

that is it in a nutshell.  I recommend that you attend one of urc's many dealer trainings if you plan on getting into total control.  There is much to learn.