Things I learned: 

1. It comes with a proper printed description that for some reason is not in the downloads, and therefore can be obtained only via purchasing the board, wait 8 weeks for shipment plus a week for delivery.  
2. The board gets its energy from the connection with the printer.  No external power source needed.
3. The jack connector doubles up with ground and pins 0, 1 and 2. 
4. A model of a printable cover is available somewhere,  presumably in Printables. 
5. If I want to execute a macro when an external switch is closed I need to solder say jumper 7 and connect the switch between  ground and pin 7. Closing the switch will create a shortcut and cause voltage on the pin to go down to a level detected as zero and this will execute the macro.
6. If I want to execute the macro if a switch is opened, i.e. the safe way because it will respond also if there is another break in the external circuit, I need to do something else, but I need to figure out what. 

Thanks!

Posted by: @ssmith

How about a switch on one of the inputs of a GPIO Board, to trigger a macro with a M601 geode? This looks like exactly what it's designed for...