There have been some reports about issues with the Updater not updating anymore. Please try the latest beta version and switch to another IP Check provider instead of the previous default dnsomatic.com. For some reason they are rate-limiting the number of requests to their service. The new IP Check provider selection allows you to choose another provider in such cases. You can test the functionality with the new "Test" panel.
Please could you add DNS Made Easy?
'id' is an internal ID assigned by them for each record.
In my experience they seem to ignore the username field - the call succeeds even if the username is wrong or blank, as long as the password for the ID is correct.
The page lists possible error strings returned - it returns 'success' if it succeeds.