If I understand your question correctly, you’re looking to connect a button (“doorbell”) at your front door that wires directly to a zone on your M1 (or M1EZ8) and you want it to be illuminated as well?
Have you found a solution? Is there any reason you didn’t buy an off-the-shelf “regular” (ie with its own chime and transformer) doorbell and integrate it to your ELK using the ELK-930? (curious as I’m considering doing this myself).