This one needed a ND on the sky.
As a consequence of the blown highlights on the sky/mountain, it looses definition. This is one of those times when too much contrast doesn't help.
Good attempt for the challenge. It's too bad the sky is so blown out. That water looks like it's moving fast enough, that you could have used a much faster shutter and still had the effect of a slow shutter. REally good use of composition though (S curve that exits the lower corner).