Thanks so much!
You can sell the special items to merchants for gems, or give them to Arthur in Deep City to get rewards.
Ah. That helps!
I'm finding that I seem to go about things in the "wrong" order, and that sometimes gets me irrevocably stuck. Mostly, this seems to happen when I see the obvious path and think, "but maybe there's a secret over here..." Then, I end up finding what seems like an unintended path and having no way to get back. Save often, people! :)