Turns out the map I did for the competition didn't quite (actually by a long way) match up to the Author's vision of the world. I've been re-doing it with his input over this week and this is either the final (or near final) result. Strangely enough I was in the process of writitng a tutorial about how to make maps like these (it's pretty much non-destructive, so really easy to edit which is very handy in situations like these when changes have to be made). Once I've finished the map, I'll finish the tutorial and post it.
Cheers
Ravs