I have 2 US-428 control surfaces and am trying to get them to work with Sonar Pro. I found the controller installation program, which includes the us428, but when I set up the controllers in preferences, nothing is working. I can get some of the functions to work by using the learn function if I load them as Cakewalk generic controllers. I have windows 10 pro. What must I do, or is the fact they list the US-428 just a mirage?

They work fine - I use one for a cheap control surface. 
https://www.cakewalk.com/..mentation?product=SONAR X3&language=3&help=ExternalDevices.03.html
 
Somewhere along the way they quit supplying the instrument definition file for the US-428 but it is still available on the Support site for download somewhere. 
 
Not all of the functions work of course but the basic stuff is there.

Thank You