downloaded the sliprock pearl icc to photoshopcc/color synch,
opening the print menu, selecting the slip rock pearl icc, the preview space shows almost completely blank, just a vague outline of an image which cannot be visibly identified. ?????

Chuck,
My apologies for the difficulties you are having with soft proofing. The 'simulate paper color' is not a part of the ICC profile, but a function within the imaging application (Photoshop, Lightroom, etc). The program looks at the white point data, and attempts to display it on screen. The problem arises with the metallic papers because they are not 'white', giving you either the mostly white/blank (Slickrock Pearl) or the dark gray/blue (Slickrock Silver) preview.

To see a more accurate print preview, un-check the box for 'Show Paper White' and your issue will be resolved.