Okay, i'm continuing to try to get a handle on this player.
I can see why Randy would sell his front end in favor of this one, especially as I think Randy loves a tight and focused sound more than I (I admit to liking more a relaxed and laid back sound, sounds more like actual music than reproduced music to me that way). This machine with Steve's mods really give you the real deal on the disc. Which often is not a good thing in my case; I have thousands (literally) of discs that could use more sweetening than this machine will allow.
I've discovered that the listening fatigue I had experienced the first weeks with this machine has somehow dissipated. The six weeks of running constantly under my bed must have accomplished that.
In comparison to my other favorite sources, this machine remains a bit more "forward" than I'm apparently comfortable with, and there is less bass presence* than I'd like. I've rolled tubes and these features remain within the tonal changes that tube rolling brings about. . . . I think this machine is very neutral and is showing me the problems that I have with my system and room. I do tend to shelve down the ribbon tweeters in my RL2s a lot, and the geometry of my large room must be hampering me. I'm not really able to add room treatment and I'm not changing speakers soon it appears so. . .I'm trying to get used to this as I don't want to add a subwoofer (don't think that's the cure) and I really do want to like this ZCD machine. It's a quality playback device, no doubt of that!
I've ordered a fresh tube of my favorite tube and I'm sending my ZBox back in for attention (and the ZCD DOES sound better with the ZBox than without). I'm going to keep spinning discs and listening and "acclimating" myself as best I can. I really WANT to love this thing!

* well, maybe there's less bass presence. Maybe there's just something that's fundamentally different in the way this player interprets things than the DVD player sources (DEC685, Sony ES Blu-Ray player, NAD T585) I've been using and used to. DVD players always seem to present cds in a certain way that is a tiny bit smoother, warmer, than dedicated cd players, at least to ME in my system. I do miss a tiny rounding, a tiny bit of warmth that I think I'm used to and just isn't there with the ZCD and shouldn't be if it's a "coloration" of a DVD player. . . . The Decware products are just so clean and clear, I mean the ZCD, the CSP2, the SE34L Monoblocks just don't color the sound. . . maybe I'd be happier, get that touch of warm sweetening I seem to be missing, with a more classic sounding tube amp, Eddie V's, a revamped vintage one, etc. with the ZCD giving me the unvarnished truth on the disc? Something to ponder I guess.