Chris - I liked your entry - especially the simple, straightforward composition and layers created by the hills and clouds. I think you have a bit of noise going on, especially in the cloud layers. That probably cost you a bit on the score. I would give Photomatix pro a go (you can download it for trial) and see how it treats the images). I have noticed a lot less noise issues with Photomatic Pro in their latest version.
Well done enough, but something about it is not really grabbing my eye. Perhaps my gaze is not being drawn through the frame to anything in particular.