I would use mountain utilities to load a profile into the FCB1010...it's pretty straightforward, the thing is you will need to access the midi in/out of the FCB1010 and if the Kemper is blocking that maybe use the FCB1010 midi alone...not sure how your Sonar see's the FCB but thats the issue, in order to load a profile to it Sonar needs to see it...is the Kemper the only midi you use?
My point is if you can load the profile to the FCB it is capable of storing it as a preset regardless of what device you want to control with it...maybe set it up first and then put the Kemper back in the loop.
Here's a linkypoo to mountains stuff...
https://mountainutilities.eu/fcb1010