I finally have the hardware I need and I'm working on it, but no luck so far. I was really hoping that since the OS is in memory now, just getting the box upgraded to the latest software before installing a 4TB drive would solve the problem but it doesn't. It's writing Block0, the new APM (more on that later), and successfully creating the /var & SQLite partitions, but it doesn't create any of the MFS structures and just keeps looping into an error message / KS57 circle. I just bought a lifetime Pro and a WD40EFRX, so I can't afford another $350 right now just to see how Weaknees did it. It's obvious from looking at what I've seen so far that TiVo intended it to work (at least in the future), but there's still a bug somewhere.