I have LEDBlinky and have custom lights per system (like console games, ex. NES A and B red) and per games like NEO Geo, active buttons light up.
Have taken me ruffly 2 yrs to get completed, but I have RGB buttons, which makes it even more time consuming but revarding in the end.
When scrolling in HyperSpin you see the buttons directly and they stay when the game is started.
You want to pay for LEDBlinky to get rid of the nag sceen and support Arzoo
Then I found the superb program
RocketBlinky which generates all (say 90%) of all MAME and other systems for you!!!! Awesome!
Then you get inside the LEDBlinyControl.xml and edit it for new /missing / faulty titles for your own liking
http://forum.arcadecontrols.com/index.php?topic=150224.0Cheers!