[Marco78]

I think I managed to lessen the problem by careful moves of the Skin smoothing and Texture sliders, under the Skin workflow.  For the texture slider, I actually tend to give it a negative value: sometimes down to -30 depending on my need.
Perhaps it is also a better idea to work on Portrait Pro after all the other adjustments have been made, such as sharpening, dodge and burn... etc
Sharpening on a skin which has a lot of 'scales' or 'craquelure' like texture due to uncareful tweaks on Portrait Pro, will only make it worse!