Well, started the patrol with Harbour Pilot enabled> saved game after 7 min. running with Pilot> quit to main menu>loaded saved game>enabled manually harbor pilot> the route was continued=that's perfect
but:
when quiting not to main menu but to windows>loading the saved game>manually activate the Pilot> the Boat made a large Circle (or ellipce)to starboard as if returning to some point, than again returning to cource and proceeding the route



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That was done by me twice with the same result

very interesting, very smart system. Lets recommend it to NASA for far space travelling