(EDIT: are these actual SW concept art by Cantwell?)
Yes.
Right.
Well that at least gives me some insight to the visuals of the first draft, but these NASA spaceships with the weird wings still remain a mystery.
EDIT:
I actually found one of the images described in the book on the webpage with the interviews that you linked to. Although you sent me the link several hours ago, I decided to look at it again and scroll down past the videos to see if there was something else interesting written, and after having scrolled past a whole lot of photos, there it was, Lucas’ red Frazetta-like cover for first draft.
It’s quite rare apparently, even the guy who interview Cantwell seemed surprised, and wrote that he couldn’t even find it elsewhere on the internet via a Google Image Search. And who actually made it is still a mystery.
(I’ve added the cover art to the first post btw)