Just saying that I've got my interface PCB working. It uses Charlieplexing which allows me to control all buttons using just 7 lines - which allows it to work with the ESP8266 module which does not have as many GPIO pins to use as the arduino.
It works with both the arduino and ESP2866 module when working like the original MK14send program - just amended o handle the Charlieplexing.
My hope is to load a web server into the ESP8266 which can store the program and allow you to select the program to load from a web page.
I'll let you know how I get on.
