Is it possible to use Screen-Position based UV's in UMG?

Has anybody had any luck using discreet UV math for UMG Objects?

I’m trying to essentially put a texture grid behind my buttons or borders or whatever. But UMG doesn’t seem to pay any respect to the UV coordinates laid out by the material, like Screen Position etc. I can tile an image using TexCoord’s, but not use anything else. See image below for details. I want the rest of the Texture Samplers to use the UMG-specified coordinates.