Former TheGIA staff member was kind enough to help confirm that the newer fanart might have been the first publicly posted, however.
Another candidate for the oldest Krystal fanart has been found. Can't confirm yet, but there's a pretty good chance.
A Nintendo Power envelope art from about two months after Dinosaur Planet was first revealed. Where are you, Leah from Las Vegas, Nevada?
The first time I've seen "trailer" footage of Dinosaur Planet, though this footage is well known to Dinosaur Planet researchers.