In today's news post, found HERE , they state "Playing a Melee? While your opponents battle each other for board position, you can slip Ser Davos Seaworth (The Great Fleet, 28) into a Military challenge to tilt its outcome in the direction that suits you best…and grab a point of power from his Renown"
I thought the naval rules dictated we had to be an attacking or defending player to participate. I also thought that even if you did manage to get a character into an opponent's challenge in a melee that even if the side you were participating on won, that you couldn't claim Renown since "you" did not win the challenge.