The Skins are indeed opaque but they're thin and can work with a variety of other cases, such as crystal cases. I believe that the Skin should work fine with the Invisible Shield, but I have not quite figured out which to apply first.
If the Skin is applied first, followed by the Invisible shield, the overall finishing should be nicer but there may be slight problems with the fitting of the Invisible Shield depending on how forgiving it is. The Skins are very thin at about 6-8 mils thick (10 mils = 1mm) but this slight 'thickness' may mess up the alignment on the Invisible Shield.
If the Invisible Shield is applied first, the Skin should fit fine on top as the Invisible Shield is even thinner, but I think that the presentation will probably look nicer with the Skin applied first (if it fits). It's up to you to test.
