Greg responds...

1. I couldn't remember any reference to "Ussex", so I just reread the entire script to "Awakening, Part Two". There is no "Ussex". But Xanatos does have a line where he says "I learned about the castle and you six from an ancient book that recently came into my possession". Could the words "you six" be the "Ussex" you're referring to? Anyway, Wyvern is a fictional location, but in my mind, it was always on the west coast of Scotland. It was loosely modeled on Tintagel, a Cornish stronghold associated with King Arthur, where I've had a couple of near-religious experiences.
2. I don't find it that hard to believe. 1000 years had passed. Frankly, I find it slightly harder to believe that Goliath and our gang survived that long intact. I think we may all owe Hakon and the Captain a favor for that one. I'm sure there were a few more scraps here and there. I'm also sure, Xanatos collected any worthwhile piece he could find. But I don't expect there was much.