Callum, that opening area looks great! I'm just wondering, what stuff is there to do in it? I know beauty is its own merit, but eventually I'll just thok right on past it and not give it a second thought.
I think the shadows the trees are casting are a bit too dark.
The water under the tree's shadow is too bright, it should be a little darker.
I've come to terms with the SHALE textures on the outside, but I really think you should use a different texture for the caves, preferably one that actually makes it look like a cave.
Stuff
Pfft, Chary's probably going to use custom music on the map that he makes on his own, that's about +5 points in the voting. Give up guys. xD