> I don't believe its a graphical update like you described, though; despite the > protection changes the game plays the same afaik.
I agree, but they might still be interesting to see.
Many years (10 ?) ago, I exchanged a lot of emails with Dan Gorlin (the programmer behind Choplifter), discussing the game and the special version I was looking for. The "1987" version I have been looking for, isn't a version of the game he knew about or had seen.