You should be able to get it up and running pretty much automatically using the Insert Synth Assistant. Just go to the Browser (press B), click the Synths button in the browser (which shows the Synth Rack), click the plus sign button (+) then select Addictive Drums and the Insert Synth dialog should pop up.
Then you have some options. I'm assuming you want an audio track for each kitpiece in AD. Choose "All Synth Outputs = Stereo". It'll give you a stereo audio track for each kitpiece, the overheads, the Aux outputs, etc... as well as a MIDI track to put your MIDI clip into (so if you have a piece of material you want to use just drag it into that track... it's the one with the icon that looks like an old DIN style MIDI cable connector). All your outputs will be set up automatically and be routed directly to the Master bus (which you can change if you want).
Then go to the AD Window/Properties page, choose/load a kit and you should be able to play back your MIDI clip.
Doing it manually is a bit of a pain and requires quite a bit of knowledge/fiddling which is why the Insert Synth thingie is there to do it for you. Once it's set up save the project then go through all the track's Input/Output/Channel/etc things to see what goes where and you'll probably get a better idea of how to do this stuff manually if you so choose to in the future.
If I have misunderstood your predicament my apologies. BTW the Insert Synth stuff is in the manual tutorials so it's worth going through those if you haven't already but I think they use a Simple Instrument Track instead of the multi out method. There is also a video on inserting a multi out drum synth on the CakeTV section of this site that helped me immensely (but he's using Session Drummer but the set up is basically the same).
Cheers.