Finished loading Inkscape 0.92 on my Mac. Followed directions to add Symbol libraries and create 2. Now symbols do not show up in the documents placed, only a white box. I have checked the Fill and Stroke settings and Opacity settings, as listed in another Forum post.
In the attached screen shot, I have placed and edited a square and some text. The white squares are Symbols from AIGA Symbol Signs, Gnome Icon Theme Symbolic (Apps), Flow Chart Shapes, and the Furniture_Icons that I created.