Well I've done a complete re-install, with i386 image again, and have been having some success and have actually added a media director and can see my pvr from another room. In hindsight, I think I know what I did to brick my hybrid/core (just a theory), and thought I'd share in case anyone runs across this.
I remember I was getting ready to start up my media director in the living room for the first time (hybrid in separate room), so I did the "setup diskless MD" and let it run it's course. I then thought, well before I do that, I better set up the pipes better in the rec room (where the hybrid is), so I can control the equipment once I get the media director going. Well, in the course of setting up the pipes, I remember relaoding the router, and somewhere along the way, I remember looking in the restart screen on the web admin page and seeing 2 entries instead of one, "core" as the core, and "hybird/core" as a media director. I thought this was odd. I had only seen the "core" entry before, which makes sense because I only had one machine on the network at the time. So perhaps the pipe definitions pointing to themselves confused the dcerouter so much that it couldn't resolve it. (?)
So my lesson I took from this was, don't do the "setup diskless MD" until immediately prior to actually booting it up, and don't do anything in between setting it up and booting it for the first time. That is, I HOPE this was the cause, because I'd sure hate to do this all over again.
Dave
Dave