Hey,
Way cool you bought a KN-3000 instead of a Yamaha. I know that a KN can react on brightness changes but right now I don't know the SysEx code. Although I got some connections to professional Musicians using a KN-3000 so they might know this code.
Another thing is that using your keyboard in combination with Cakewalk is not great. The hearth of each Technics KN workstation is its composer, so use it. Of course you can use a sequencer but if you do take Cubase. It is more friendly to your technics than Cakewalk. Use the Grid Function to implement your control changes.

I hope this information is a bit usefull for you.
Greetings
- ZYX -

e-mail: DJ_Dominator@CyCosmos.com