I don't know if Group Cooldowns works anymore, but I was using that to add a counter to certain slave abilities. Specifically, back when Exorcism had cooldown but AoW didn't.

Basically, I had a button set up like Ualaa and Zub {but set up as a mouseover in HKN} that was just an empty macro showing the Exorcism icon on my main with the Group Cooldown overlayed on top.