Hey Dreamer, are you using any version of Poser 11? I'm not up to the latest version, but am using an 11.3 version and one of the goodies added with Poser 11 was the ability to add "layers" in the Material Room.Yes but you can't save the mask by its self to apply over any coat the way an LIE can, that is where you need the scripting to get it to work. There use to be a script in the market that did just that but just when I was starting the Pintos it got pulled and I had no luck trying to contact the vendor so the poser side got shelved
You need to be on the Advanced tab of the Material Room, and you'll see in the screenshot below a button to add a layer to the material setup. I've used it several times, and I think by default most use 2, or possibly 3, additional layers to create the desired look. There's also a button to delete a layer, but it's greyed out until you add additional layers to the Base.