All right, there's a lot of extraneous information here I'm going to try and cut through:
I'm running MC17 on my desktop computer in my home office (in my basement).
My family room is just outside my office. A Sony STR DE595 audio receiver and WDLive.
I would like to connect my computer to the audio setup I have in the family room. In other words...watch MC17 through the plasma while the sound going through my audio amp. All this without loosing anything I currently have on my desktop as I spend a lot of time there.
OK a few options:
For full MC17 experience:
1. Run HDMI from your office desktop to the family room. Also run a USB IR or RF remote cable from the computer to the family room to be able to control MC from the family room. Use zones to control output selection (office vs. family room). Pros: Cheap, robust, energy efficient. Cons: Have to run cable, may run into some problems with multitasking on office PC while playing video in the family room (especially with CAD software).
2. Build a dedicated HTPC and use library server to access the desktop MC library. Pros: Robust. Cons: Not cheap, will need both PCs running if you are accessing files remotely. Could duplicate libraries as a backup-replacement onto both machines.
For partial MC17 experience:
1. Set up the WD Live as a DLNA device in MC17. Access MC17 via your phone, tablet, or laptop to control playback in your living room. Pros: Easy, cheap. Cons: You lose MC17 theater view, WDLive is sometimes hit or miss for video playback.
There are other options to save some work (wireless display, wi-fi enabled remote (or Synergy)) but these will raise the cost dramatically, and I wouldn't necessarily call them "robust" options.