Santa is now beginning to move and "control" things in the display. Pin 13 of an Arduino seems to switch on and off during the boot sequence and that plays havoc with an attached relay. Tying a 2K resistor (gnd to relay board input) doesn't seem to help--the line is pulled up and down. I shifted to pin 12, but would like to know what is happening with pin 13.

At any rate, things are moving.