Thanks for the replies!
I have made some progress, though not quite where I wanted to be...
First thing I did was check to see about the DCS/DCC switch, since I've gotten at least one engine previously that wasn't set properly - it was fine.
I've tried a dedicated programming track with a recently displaced older TIU, after setting it to TUI 1 (Already at 4.20). Recover engine did nothing - was kind of odd with no messages, just a long wait.
Tried opening up the unit and resetting the 40 pin connector. This was my first time inside a PS3 engine - my, the wires have gotten smaller! Partial success at this point - the engine would register, grudgingly with track errors, as an engine with no name in the remote. Could start it, turn on/off smoke, but no name is disconcerting.
Any suggestions from here?
Barry - I had gotten your book years ago in electronic format - just can't seem to find the receipt. Keep on meaning to call to see if I can get a resend, but keep forgetting during business hours. May just buy it anew.