I have completed my em to arduino its is really easy just need to do some wiring and add the bits i used. The tricky part is the LED part i found. It was not the prigramming but remembering what each led address was. next time i will label every 5 LED so when i try to find a specific led its easy. NOTE i do not use any scanning of switches or LED as the arduino has lots of i/o ports. Next stage is to build a backbox, just found score reels so i am ready to go. see bjmclrn arduino for some more info.