I have tried a stereo AD2 Master input "at the top"in the track order, and also one where I have two AD2 Masters, one with input from AD2  left and the other right. In every case I have simply sent their outputs to Master.
 
Then I insert audio FX...say, Sonitus Delay. All the delayed sound is in the left speaker. This is regardless of what input I choose for the AD2 Master (which sorta makes sense) or where any instrument is panned. Other FX are also going left.
 
If I place the same FX in an individual drum's track, the FX behave OK. But except for special occasions, that would be ridiculous and unrealistic, IMO.
 
Any ideas guys?