Well, it helps being an electrical engineer 
And its really just my version of commercially available scoring machines, with the operation programmed to do things that I would like as a referee vs what they do now.
I'm still working on getting the touch lights working. I started with just reading the serial output of another scoring machine to turn on the remote lights, then added to it to show the score & time, then while waiting for that machine to be updated to accept time start/stop commands (so I didn't need 2 remotes), I created my own time running code, and am now adding the touch functionality to make it a totally independent machine.
Somewhere in there I came up with the remote also. Started just getting wireless to talk between 2 arduinos with the example virtual wire, then added the keypad library code to be able to send specific characters, then added sleep mode and wake on interrupt, then changed to lower voltage promini with Li battery, then added battery charging circuit.
So, small steps, get it working, add to it :-).
I have code in place to sound a buzzer, waiting on a little speaker to arrive to add that in.
Am working on touch circuits now. Have something working pretty well for epee (fairly simple, button closure on the end of the weapon, is either closed against non-ground (good score light), or against something grounded (so no score light). Trying to get more comlicated sabre & foil working, where you have to score on opponents lame (outer metalllic jacket over the fencing uniform), but have situation where if your weapon touches your own lame lights have to off, but can score & be scored on while that is happening, and there are strange time restrictions that the code has to account for.