The file is a shader file . . . In MAYA, open the hypershade, go to File > import, and then import that file into the hypershade. Then you can apply the shader to the background. I would probably use a plane, or maybe create a sphere with the camera inside the sphere and the material applied to the sphere.
This star shader is actually made from the "Granite" shader, and the colors have been changed, and the 3D texture warped to prevent a repeating pattern of stars.
"The Sage as an Astronomer: If you still see the stars as something above you, you lack the eye of knowledge." Friedrich Nietzsche