Create a drum map. Go out to like, measure 8 or so, and stick a kik drum (or something) in there so the track is at least 8 measures long. Select measures 1 thru 4, and set it to loop. From the drum map, press play, and add your hits as it loops. If you're in the drum map, you don't have to have the track record-enabled. Just stick stuff in there and it'll play. As far as getting rolls in there, make sure you have the snap thingy set to 32nds, and select the little button that says 'move by'. If you still can't get the timing right, select 'absolute time', which allows you to move the hits to anywhere you want. Good for getting flams and faster rolls. As for velocity, once again, use the drum map. You can change the velocity as easily as clicking and dragging the velocity up or down. From there, it's a matter of thinking like a drummer. If you're playing a roll on the snare, not only are you hitting the drum in different spots, but you also have a difference in velocity and intensity between left and right hands. Try the loop thing, dude. It beats the hell out of sifting thru hundreds of random patterns in Slicy Drummer or Session Drummer.
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