I've just posted some of the images for comparison. I think most of the illustrations in the book are completely new, though some bear a close enough resemblance to scenes in the story that I wouldn't swear they weren't from publicity shots or similar. I think the capture and rescue of Barbara get a lot more emphasis in the book, partly I suspect because Whittaker obviously shipped them, but it wouldn't surprise me if it is also because this is where our protagonists actually get to influence the outcome of something.