I would say probably my worst problem was "I wasnt there"....lol.

I process my work for what I remember of the scene when I snapped the shot.

I process both peices of the blend in RAW to start, one just for the highlights that are over the top. You had just a few areas in the main fall that were unrecoverable. But if you blend it right, you can blend the water hot enought to not look over the top and if the transistions are correct, they are pretty effective in hiding the hot spots.

Then I processed one igonoring that bright area, and only concentrating on what was best for the image as a whole.

Dragged the light one over the dark one in photoshop.

I do use the BetaRGB color space on my computer that helps a tad with my histograms and what is available when working on my peices. I highlighted ONLY the brightest parts, the main falls and the mini falls Did a 30 pixel feather on that part.

On my two shots...one looked great with only burnt out highlights, the other looked HORRABLE with only properly exposed falls (except the slightly burnt areas that I couldnt recover.

I then did a layer mask using that selection with a 30PX feather. That got it looking REALLY nice.

Then just play with the curves of both layers and the top layer...play with curves on the layer mask as well.

As you play you will start to see how certain parts of the curve affect the blend. Its rather intuitive, just play and watch....you will get the idea after a while.

You're in the area, maybe some day after you get back I can walk you through it if you find your still struggling.

Roman