Hi there,
We're using a number of Alpha Clock Fives at work for a few projects. For convenience, I created a serial wrapper library for sending data to the standard firmware.
Commands include:
-set brightness
-set font
-send millis to display as MM:SS
-send word
-send word and draw dots
It currently only works with a single clock, but you could hook multiple clocks up to multiple serial ports and work that way.