go to the application icons tab (third one down) and you'll see the list of icons that are stock for the theme. you can click on each one and replace it with an image of your choosing for both normal and focus.
__________________ The sun has left us on time, am going to read from the Encyclopedia Britannica to steady my nerves and go to bed early. I will shut my eyes and imagine a terraced abyss, each terrace occupied by a beautiful maiden. To the first I will deliver my mind and they will pass it down, down to the uttermost depths of silence and oblivion.