I've never had a problem with greenish skies. I have to brighten them up, but haven't seen them green, and I've spent a lot of time in the RS room.  Perhaps your monitor is a bit off, I don't know. Look at my gallery and see if the skies look green.

 But, the color wheel for the sky is fixed in 7.0. The colors stay, but if you start changing haze also, everything interacts so you have to be careful.