Ok, here's one final update before I wrap this up to print! I went back, made the center button separate so that it could be made into a real pushbutton OR just glued in place. A guide was added to the inside of the cube to center the button. I also added diffuser supports (see the picture) to the inside. Their main purpose it to provide a thickening wall to catch light inside the cube and help achieve the "fade" effect.