Thanks to both of you, I appreciate it.
@Ray: I actually didn't get to the top of Ben Nevis, unfortunately (a combination of bad weather forecast, lots of snow and too few other people on the mountain in case something went wrong), but the views on the way up are worth the hike anyway.
As for black shadows, I take it you are referring to the lower right corner and not to small rock shadows? The trouble with trying to pull this area is that there isn't a lot of detail in it in the first place, and as soon as there is no (0,0,0) pixel in it anymore, it feels quite wrong and the whole image lacks in contrast. But I'll give it another try, I think this image is worth spending time on.