Well now you have some options....
You can create a beat in Fruity Loops by itself and play it in Cubase using the VSti (multi) (for multichannels).
or
You can create a beat in Fruity Loops and export it to wav and then import the wav (with same time signature) back into cubase.
This is what I usually do....
I open up Cubase and Fruityloops within that. I hit play in Fruity loops and start to lay down a beat. I could also just lay down the beat first in Fruityloops and save it and come back to it some other time and come into Cubase and open FL's as a Vsti and open up the track from within there. When I'm all done, I usuall export it to a wav file, as with all my VSt tracks (less load on pc, can add audio effects, ready for final mixdown).
Sounds redundant, hope this helps, but when all else fails just play with it. You have a world of options, and you may find some I know not of.
Please reply and share what you have figured out once you get going.
Thelonius