Considering purchasing Roland TD-11KV e-Drumset and Battery 4. How well do they work together?

I am guessing that each pad on the drum set can essentially represent a key on the keyboard such as C1 or something (excuse my crude MIDI knowledge). However, there are many more cells in Battery than there are pads on the drum set. Let's just say I set up the first five cells in Battery to correspond with the five pads on the drum set...how could I switch to control the next five cells in Battery? A little side note...I also own the Lemur software for iOS devices (which I don't quite fully know how to use either), in case this may aid in my quest.

As a side note, it'd be awesome if I could export the kits from Battery into the drum module that comes with the set...is there any way of doing this in a quick and efficient way?

Your answers will help convince me if this is the route I should go through. Thank you!