As you can see from the attached screenshot, any point you try selecting (e.g. for remeasuring), the info point and the manual measure sliders always points to to the greyscale one.

I have noted that during my testing and replicated with virtual probe. See also annexed the related bcs file for your comfort.

PS: I have cheated the upload rules adding the extension .txt).
Feel free to delete it. I think it would not be a bad idea having also the bcs extension among the allowed ones.

When trying selecting a blue point

Yes - that is correct, and is as expected.
The graph has no actual concept of any point data, as it plots a calculated result.
So it therefore defaults to the grayscale, from which the RGB Separation data is defined.
The RGB lines are NOT red, green, blue points in any profile data - they are the RGB Separation error.

That is also why you CANNOT directly adjust points in the RGB Separation graph.

For uplaods of profiles, ZIP them.

Steve

I understand your view (separation is virtual, i.e not real, as being computed), but the point on the graph is the result of the blue point measuring.
I was on the wrong track as reading from the manual I see : "Double Left Click on any point in the graph opens a floating window enabling any point to be edited, deleted, or the selected patches exported as a .csv list".
Anyhow quite easy remeasuring the colour points by using manual measure sliders.

No, the points on the RGB Separation graph are the result of the Grey patch vs. the equivalent RGB patches.
You cannot select the RGB patches from the graph, as there are no points for the individual RGB patches.
Grey is the common denominator, so is what the graph selection defaults to.

Steve

Maybe I am naive, but why, when I click on the point on the blue line corresponding to (xxx,xxx,xxx) why not selecting (ref black,ref black,xxx)?
Anyhow, if I cannot select what RGB patch, why am I allowed to select the coloured points?
But regardless your implementation, I am indeed trying to spot, that I could not find that in the manual
Before signalling what I wondered whether it isa bug, I have checked the manual page and concluded it was the case.

As already stated, the points in RGB Separation are calculated results.
They are not linked to the original profile data, which is why you cannot directly alter the points.

Steve