When I was working on the Game Boy Color version of Tintin in Tibet, I also thought of doing the big counterpart. But I didn't feel like playing the same game again so short after to map it, too. So it never worked out.
But it really is a very beautiful game that deserves maps. And also the Temple Of The Sun part.
Sadly my daily time is already overfilled with other completely unrelated things and I don't feel like starting with a mapping project at the moment, so don't count in on me.