Share 'Material Library "Slides"'

When I loaded AccuRender nXt back in 2011, I remember using a wizard to convert my old AR3 (maybe AR4) MLIBs.  I used to able to search for materials in AR5 and there were "slides" showing the material colors and textures when I browsed to a new converted library.  I no longer get an image when I view an ".ARMaterial".  In the latest nXTRender (for AutoCAD2018) I now see PDFs, but no "slides" tha…