As it is one of my favourite films, I've been looking for a re-graded FOTR EE for quite some time, and recently have been able to watch KK650's attempts to remove the awful green tint.
Let me say that I think it's a fantastic effort, and I appreciate anyone who undertakes this project. And to my eyes, it is a definite improvement, and more pleasing viewing experience, over the existing BD image.
That said, speaking personally, this version doesn't quite get to what I'm looking for, which is something that matches the theatrical grading, or at least the grading in the theatrical BD. With KK650's version we've lost the green tint (mostly), but seem to have traded it for blue. The result to my eyes is a colder image, especially in the snow scenes (which is fine and appropriate), but not really any closer to the the theatrical grading. We've essentially just switched one (supposedly) artistic preference for how this film should look with another. But perhaps that was his intention, rather than actually trying to recreate the theatrical/BD grading, so these comments should be regarded as an observation, not a criticism of the work.
Again, I do believe what KK650 has done is a very definite improvement (and thanks for taking the time and effort), but that's just a personal preference on my part. For a definitive version of this amazing film that brings us closer to to the theatrical experience, I'll just have to continue to look.