Elv13/tyrannical — pull request #32 by junipergold (2014-04-07 14:46:03+00:00)
Title: Fixed error in README. First value is instance, second class.

I think the you need to use the second value you get by using xprop. With awful.rules you can match the first with "instance" and the second with "class". Tyrannical does not support instance matching but I think "class" still matches the second value.