I will be deleting and replacing this first post with all the little things I have learned from the gurus on this board, particularly David Boulanger and Michael Oborne, that have actually solved issues that I could not solve without their input.
The focus is going to be on what happens after a ‘firmware update’ or a ‘restore default parameter’, because this is where my wheels usually fall off and it takes me a week to get back on track.
I hope to also get my sonar survey boat running straight again and will post the outcome of that here too.