Alert!! Logic Pro X Users
The KeyLab 61 must be set up as controller using the Mackie Logic Control setting, NOT Arturia Key Lab 61. In controller set up, select Mackie Logic Control. Set up as shown in the attached screen shots.
I spent hours trying to figure this out with zero help from the manual or Arturia. I just got the keyboard today and I can't wait for Arturia tech to get back to me. This should never have been a problem at all.
I hope this helps others who are suffering through this setup.
Cheers!