Did you know that we have tutorials for Addictive Drums 2 accessible within the plug-in? Just click on the menu icon in the top right corner of Addictive Drums 2 to find the Tutorials menu. Besides an overarching Getting Started Tutorial there is also a MIDI Mapping tutorial, for when if you're using an e-drum kit or external midi files for example.
For even more information check out the Addictive Drums 2 User guide.