I must admit that I'm struggling to see the point of 'My Library' on the Nook UK website. Quite apart from not showing most of my purchases, the ones that it does show don't link to the content itself but instead to the purchase page of the book or magazine - the least likely page that I'd want to navigate to, given that I already own it.
With magazines, there's an 'Issues' button, but it doesn't display which issues I've bought. It also takes me to the purchase page for my already-purchased subscription.
Graham