Lit Button hack for fun? What does that mean?

It means that one of the developers wondered what backlit buttons might look like on an Empeg Car and hacked (hardware hacked, i.e., soldering-iron-and-needlenose-pliers hacked) some LEDs onto the unit.

I mean, are there lights behind the buttons or not?

No, there are no lights behind the buttons. The buttons themselves are the kind that you could insert lights into them if you wanted to, but you'd have to do some delicate soldering work and know exactly what you were doing. And you'd have to fashion or obtain translucent button caps, too.

and if there is, are you saying that they don't go on because of software?

I think the option to control them via software could actually be implemented, but I don't know if you could do it independently of the display or not. They would probably just turn on and off with the display.

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Tony Fabris