I think I know what's going on. You wrote your whole drum line using the redrum pattern (the white buttons on the redrum). In that case you need to copy the pattern to the sequencer track. Right click on the redrum and select "Copy Pattern to Track".

I prefer not to use the patterm making feature in redrum. It's useful for those that are used to using hardware drum machines and can associate better with reason that way.

You can just write notes directly in the piano roll. Click on a little drum icon above the list of sequencer tracks.