Ok man... when you're browsing around the real drums files you like, make a note of what the name of that groove is that you like. For example: "BossaBrushesFull^2-Brushes" would be the file name.

Now, when you build your song... go to the windows menu, real drums picker. To find "BossaBrushesFull^2-Brushes" I would click on "BossaBrushesFull^", then over to the right, I'd click on option 2, brushes.

That should work for whatever groove you happen to find while you're browsing around. Find it in the drum picker, select it, then click OK and you should be set.
LUCK!