You have to add Spark as a midi controller to cubase and activate it!!
but uncheck the "Spark Private" midi connections!!
connect only the "Spark Public" ones (as stated in the manual!).
then u should be able to record drums...
My way (i think the better way) is to record patterns into Spark and then drag n drop Audio/Midi to Cubase arrange window.
I think/feel that the Spark sequencer is MUCH MORE groovy and drum like, and everything sounds much tighter and REAL, than working in a "normal" sequencer.
i hope that helped...