So, interestingly, contrary to most things I've read on the web I can only get this to work if I a) enable HyperHQ to use LEDBlinky and b) launch the game via Hyperspin.
I'm using Rocket Launcher, which also has the LED Blinky path setup and told to use it, but launching direct via RocketLauncher does not seem to do anything
One aditional issue I am having however is that despite the relevant values set in Colors.ini, my coin/P1/p2 buttons do not light...
My pause button lights per the default set in the controls setup, but I can't find the relevant button there to light my exit button either...
EDIT: Just to confirm, I'm pretty certain that nothing from RocketLauncher is actually being used - for example I have a second duplicate of a mame system in Hyperspin and RL, I have told RL to system name as MAME but it doesnt - looking at the unknown games list it's getting the original system name