Assigning Oxygen 49 Controllers in Pro Tools - Need Help

Hi,

I have the Oxygen 49 and i can use it fine with the direct-link function (preset 10). But one thing i´ve always struggled with is mapping controllers to 3d party plugins in pro tools.

I am talking about midi-learn. Nothing ever happens when i press "learn" on a function in a plugin, and rotate a pan/slider on the Oxygen 49. I am sure this question is beaten to death, but please help me. I just can´t find the answer.