Stuck on Initializing Station Handler

I have successfully navigated the confusing Ambient Weather site to create an API Key and Application Key and have an Online Ambient Weather Account thing. I have attempted to add a Weather Station thing and it never progresses beyond “Initializing”. Looking in the debug logs I see:

Station WS2902A: Initializing station handler for MAC AA:BB:CC:DD:EE:FF

There are no other entries for Station WS2902A

When I receive a DATA event, I see the data and then:

Search for MAC AA:BB:CC:DD:EE:FF in handlers list with 0 entries: [[]]
No handler available for event for station with MAC AA:BB:CC:DD:EE:FF

Any suggestions on how to debug further?

As a follow up - my steps above were all done through the admin UI. Moving the exact same definitions, keys and mac address to a .things file, works fine. Something in the config through the UI is causing the difference, but no exceptions or indications.