Hold on, that's the purple you meant? On the characters, not on the snow and the sky? Because I spent all those hours doing exactly that - creating a curve, which specifically adds red to the characters and not the background and which had to be tweaked shot by shot - in the BD, everything is monochromatically blue (or rather cyan) whereas in all the other transfers, you can see, that the characters have some color and it is mostly red - if I were to turn the cyan of the BD into blue and leave it at that, it would have been super easy but then it would have stayed the monochromatic mess that is the 2004 transfer and I wanted to pull out the colors of the characters and the tauntaun.

As to the lightsaber - well, it's not missing blue - it's less blue, which is the side effect of having to pull the blues down in general and again of the monochromatic nature of the BD.