This is what I do. First, move the hue slider to the opposite of where you want it. For example, if you want to move some yellow towards orange/red, set the hue to extreme green (after picking the yellow color with the eye dropper). Now you can see see where the affected yellow pixels are. Adjust the range slider to cover what you want to cover, and avoid affecting areas you don’t want to be affected. Then move the hue slider to where you want it, and make other adjustments as appropriate.

You are welcome, Martin. I think it’s just a matter of finding a workflow that works well, instead of it being right or wrong. The Color adjustment tool and the ability to apply multiple instances of it in Aperture is an excellent way to correct otherwise tricky color cast problems. No need to create masks with the rather limited brush tool, and adjustments can be lifted and stamped on a series of images. I use this a lot to adjust skin tones under artificial lighting.