Do what you can, with what you have, where you are.
Do you really need the license? Planet building rears its head in scifi from time to time, if that's the only thing you need from the setting I'd be inclined to write your own planet building world to set the game in.
Same thought here. I'd say ditch the Hitchhiker's Guide, but only in this situation. It's just too comforting to ditch in any other. I mean, it says DON'T PANIC on the back cover.