OVROverlay not displaying a color from shader including OVRColorRamp

Hi, I'm using the the cursor timer prefab and trying to color it with a shader. If I use the Main Color attribute of the OVRColorRampAlpa shader and also add an OVROverlay component to the object the object never changes color from its white to black gradient. If I take off the OVROverlay, it will animate the gradient with any color for Main Color using the Color Ramp Offset attribute of the shader. This is insufficient for me though as I'm using a different OVROverlay in my scene that the cursor should display over. I'd like to avoid the underlay as this adds extra overhead (or so I've read).

Does applying colors via a shader not work with an OVROverlay?

Thanks!