The default layer is blue backlit and the Layer key toggles to the "red" layer. We've also placed in stock die-cut labels for this layout, with the text color suppressed for the inactive layer, while highlighting the text for the active layer.
Current layouts are based on Eos version 2.3. Changes may be needed to use them with older version of software.
X-Keys are a product of PI Engineering http://piengineering.com/xkeys/xk60.php