Have you tried creating a custom material with the properties of the screen? When doing so you cna set the density to what your material is, then you just have to create the part you need and give it should give you a proper weight for the sized part you have created.
Do you know the name of the material for the screen?
If you know the weight per square foot and the thickness, then you can easily calculate the density. which you can set in your part file, or create a custom material with the correct density. then SW will directly calculate the weight of your total screen.