Thanks for the side-by side. I guess you and I have different ideas of what ruined means, but I
clearly see that what you worked with in CD7 is
not what you get when importing the clip PD18.
It's also fully consistent with PIX's and my experience of opening the 10-bit HDR clip in different apps - each one is different from all the others.
I don't know if this is specifically a PD18 issue, but I agree that CD and PD must treat this clip identically in order for color grading to work. This should be submitted to CL so they can investigate and figure out a proper solution.