Must resist M:tG. Boardgames are my methadone :)
Why do you say that trade with the free cities is not applicable without Clash of Kings?
Also, it might be worth including that you cannot enter neutral ports and when a port becomes neutral all ships in it are destroyed.
Actually I think you are right. It would work fine w/o CoK. I just thought the rule referred to a Westeros card from CoK,but clearly it doesn't. I'll correct it at some point. Thanks.