The problem is if you get Himalayas before Everest, because you can't see Nepal any more. Have to skip past it unless you're really sure of where Everest is without national borders.
I got lucky with Everest (I guess the tolerance is set higher so there is margin for error. Newfoundland I tried to click without clicking on the Appalachians but I must have been a pixel or two off :(
Ok let's try again ;)
In other words, you can click on an area already green if it's part of the answer to guess without losing a whammy.