Your description of the setup sounds like you're talking about something completely different than the Rio Reciever's intended purpose. For instance, you want to control a centralized stereo from the remote receivers. This isn't what the Rio Receiver was made for.

See, the Rio Receiver is the stereo. It's the thing that plays the music, through its own speaker outputs. Each receiver plays different music in its own room, from a centralized networked hard disk. Your system of complicated remote controls is completely the opposite of its intended function.

This rube-goldberg system of remote stereo control... Is its only purpose for music-playing? If so, I say throw it out completely and do nothing but a system of receivers. Either that, or keep it like it is, install the receivers as a separate thing, and watch the old system gather dust.