Just in case some has the same question, we were wondering on how to change the Welding Material path when using the Open (Import weld material data from file) to have all welding materials in an specific folder and for us it was not too explicit that the pro_weld_params_dir can do that. I tried because I saw on another post that it could modify something related to symbols.
However after reading the config options for welding we found it.
<current working directory>*, <directoryname>
Specifies the directory to search when a weld parameter file is needed.