@Douglas-Kryder @ccs-hello One more point. I've not yet metered the O2+ in the troubled dock configuration. Have only "known" lack of power up by lack of LED, basically not knowing all of the facts. Just got out a USB-LVTTL converter. Will connect later today to tty0 in breadboard dock to see if I can reflash. If so, the O2+ device may emerge from some hosed up state that prevents full boot, or perhaps even continuation past very early boot, to come up in a healthy state that will work in all configs.