The SceneTexture node always returns a black color in my UI Materials.
Also I dont think it’s possible to render UMG Widgets to the custom depth buffer? At least i can’t seem to find a way to do so.
The closest i came to getting access to other widgets within the material was by using a RetainerBox, which gives you the option to pass all its contents into one Texture Parameter. But with that i couldn’t figure out how to determine overlap areas, as this is just one texture.