There's nothing really flash about it, it just lets you input the names of your textures, press a button and it creates a simple material for them.
There is a material file tree in there, which parses the .mtr files in your materials folder (they've got to be extracted), and if you select one of the files from that list, and press New Material, it'll add the material into the bottom of that file. It's really only meant for adding things into your own material files though.
