The tune-to sign works independently of the other light controllers. It doesn't receive commands from xLights nor Falcon Player; the tune-to sign does not play shows created by these. Instead, the tune-to sign relies on files on the iTwinkle website.
When the tune-to sign is powered up, it looks for a file in www.itwinkle.org named messages.txt. This file contains a list of messages for the tune-to sign to randomly display. There can be up to 55 messages up to 75 characters long. To change the messages that the tune-to sign displays, simply change the contents messages.txt file on the website, then reset the tune-to sign by disconnecting power, then apply power again. Messages can be displayed in different colors; prefix each message with a three-character color code such as "RED", "BLU", "YEL", etc.
After displaying each message, the tune-to sign checks the website to see if anyone is actively controlling the lights. It does this by reading the location.txt file on the website. If this file shows a different location than the previous time it checked this file, the tune-to sign knows that someone is actively controlling the lights at that moment. It then uses the contents of this file (city, state and/or region) to display the visitor's location with a message such as "Lights being controlled from Paris, France". After this message is displayed, the tune-to sign goes back to displaying random messages again.