CS6 - Random button highlight help request

OK, I’m trying to make a simple Flash banner in CS6 using AS2.
I want the selection of buttons to randomly highlight until the user rolls over any of the buttons, at which point that one is highlighted and the random animation stops.
I’ve attached the totally broken version I’m working on that I cobbled together out of code I’ve found online, I’ve got a vague idea of what script I should be using but not much else!
I would be very grateful for any assistance anybody can give!