How to add surface Imperfection to Glass in Cycles? I'm looking to add a surface imperfection that I got from Poliigon.com to a glass that I'm making. 

The surface imperfection is off water droplets. I want to create a condensation sort of look to my model. I'm not too sure how add it in the Node Editor though. 

Can anybody help? See below some pictures of the Surface imperfection, my model, and my current Node layout. 

Many thanks,

Karl.
I have figured out how to add surface imperfection to Glass. It´s pretty straight forward, and not as complicated as I made it.  

Basically you add a texture image and put the normal map there and link it up with the glass texture.

See below the node Layout.