I posted the message before this before I went to work and just left the phone to run all day looping through whatever. I arrived back only to find the phone registered. I have no idea what happened, but I tried to add another extension and test the long/short password issues, and now the phone is looping again.
update, I waited 10 more minutes and it worked
I’ll continue to refine my settings and report back.
Observations
Strong passwords are allowed by this model of phone
Seemed unable to receive inbound calls unless
<voipControlPort>5060</voipControlPort> was set, so had to change back from 5160