As far as I know it never existed. The new Utility is different from the old one, it has the same "look and feel" of a certain competitor (D....) specially the network view showing the up and down link speed between each Powerline adapter. This other company has an OS X version. I tried, but that one doesn't show the TP-Link adapters despite they are problably using the same chipset. As the look & feel is simular, I have a suspicion the chipset provider gives OEMs some libraries or a reference application.

So +1 for TP-Link releasing an OS X version.