Michael Becker of Imagic answered to this question as follows:
"We didn't think much about it. We were working with a very talented painter and he did a great painting of demons over a moon, so we used that when it was finished. Nobody particularly loved the first box art at that time; I guess it's something that had to grow on you ;o) I kept the last rubber demon and gave it back to Rob several years later. We put it up on the pfmagic Christmas tree for a while. A couple years ago I 'returned' the Star Voyager model to Bob Smith at the Classic Gaming Expo, after a long orbit of the solar system. He donated it to their museum."