At the bottom of the addon panel is the Options button.
Click it to open the preferences window and set some general parameters.
It is possible to choose the type of material: Nexus or simple PBR.
Nexus type builds a complicated setup of nodes that allows all the advanced functions of the addon.
Simple type, on the other hand, has a basic node structure, which is easier to decipher and modify at will.
Both node trees can coexist, even in the same object.