When I did the wiring, I chose to use jumper wires to connect to the proMico rather than soldering directly to the header. I was glad that I did because the USB connector on the pro Micro broke and I had to replace the board. At any rate the jumper wires extended below the bottom of the case, so I added some rubber feet which not only fixed that issue, it made the box more stable.

I cleaned up the MacroPad sketch and created a Configure_MicroPad sketch to help calibrate the linear hall effect sensors (see Calibration log). I also added auto repeat functionality.