To get these node groups into another .blend file. First, go to the file you want them in then go to file>append or link. From here you can navigate to the Shaders Plus .blend and choose the node trees or materials. For information on how to use these masks and material settings, please refer to the product video. Please refer to the Blender manual for further information on appending here.
Note: One should always assume that all group nodes need a texture coordinate with the generated output plugged into the vector event though some materials do not.
Note: Always assume each node needs a texture coordinate with the generated input even though some do not. The HDRI that is also in the .blend file was created under the creative commons license 3.0 by deviantart user zbyg and can be found here.