(Posting this here since it is a bit off-topic for the original thread: )
With which PiTool-version are you / is he working with?
As mentioned, at least in .086, each new “apply” overrides the ones before…
I noticed this when using @Jien1963D 's calibration image:
My display is 1 level too reddish - so I decreased the red contrast by 1 ( = “-1”). When clicking apply, the colours got okay - but the overall contrast and brightness level was reduced, too.
So I retried it:
1st, overall contrast +1, apply => Contrast got better, but far too reddish. Okay, no wonder, red contrast was +1, too, this way, first.
2nd, red contrast -1, apply => clear grey shading, but bang, whole contrast reduced.
I died a second try, this time with brightness, because this doesn’t affect colours:
1st, overall brightness -1, apply => whole image got darker, but reddish again.
2nd, red contrast -1, apply => whole image got brighter again, though grey scaling was ok.
Retried it with other contrast and brightness settings twice again, just to be sure. Always same behaviour.
So it would be nice to know, whether this happens to others with .086, too, and whether it is related to .086 only. Since I have updated to the new beta firmware, I don’t want to try any downgrades.