To use correct the tool you can APPEND into YOUR SCENE:
- the nodes that you want to use (File - Append - SMART PBR PRO 2.0.blend for Cycles or EEVEE SMART PBR PRO 1.0.blend for Eevee - NodeTree)
- the complete material (File - Append - SMART PBR PRO 2.0.blend for Cycles or EEVEE SMART PBR PRO 1.0 for Eevee- Material)

You can use SMART PBR PRO 2.0.blend (for Cycles) and EEVEE SMART PBR PRO 1.0.blend (for Eevee) to check all the possibilities of the tool with many lighting setup or the LIGHT SETUP SCENE 2.0 to check your model in a nice photographic setup asset pre-lighting.

In Blender 2.8, using Eevee engine, remember to:

- in the Render tab in the Properties Editor, activate the Subsurface Scattering flag if you need to use SSS effect;

- in the Render tab in the Properties Editor, activate the Screen Space Reflections flag in the Propertie Editor and the flag Refraction in the panel you you want to obtain glasses. Otherwise, in the Material tab, in the Settings panel, set the Blend Mode as Alpha Hashed and the Transparent Shadow if you want to simulate the caustics.

http://www.blenderhighschool.it/smart-pbr-pro.html

For videotutorials:  https://www.youtube.com/playlist?list=PLN8XI7kk-4xS-xQ4IjbSEhqx7NgwlzWv7