Hmm, "installed by a marina..." You mean someone at the marina did it?
YOU need to trace the wiring
to assure yourself they did it right.
In any phase of life, if someone installed something for you, would you go out and get a new replacement if it seemed to be installed incorrectly because all the features didn't work? I doubt it.
Engage yourself, learn something new and find out how it is supposed to be wired, then check how the yard monkey did it.
I'll bet they did something wrong.
If they didn't, I'll eat my hat, in public.
In addition, those old Link 1000s had "issues", but you'd need to be more specific than "some features don't work." If you do, we can help some more.