I actually think there are a few too many steps in that SVDL. Why bother with all the inverting and creating a group for what you don't want when all you should have to do is create a group for what you do want and add the materials to it and spawn a prop? Maybe I'm over reading what you said but it seems unneccesary to me to go to all the trouble of inverting what you don't want when Spawn Propps will create props for every group and if you have a group with just what you want in it that's all that's needed.