Main heads up is to make sure "Load out of Date Addons" is checked in WoW. If you don't have PQInterface showing up in the Addons pane, make sure you have PQInterface folder copied to the WoW Addons folder. You will know you have PQInterface loaded when you see a bar down at the bottom of the screen above your actionbars.
After that, make sure to have PQI_Data.lua in the DATA folder of PQR and your done.
P.S. This is the wrong section. Should go in the Questions and Help forum above this one.