The original is very useful but I still had to spend a few more hours to figure out the rest, so I'd like to share the complete solution here. This answer is for a MacBook Pro running MacOS Big Sur and KRONOS 2. There is no additional driver required.
Go to Settings, click on the Audio tab.
- Driver: Core
- Audio Device: KRONOS_USB_L&R
Click on the Midi tab. Choose Inputs subtab.
- KRONOS (KEYBOARD): Port A
- Kontakt Virtual Input: Off
Press PROG button. Press the first ">" on top-left next to the patch name for "Bank/Program Select". For me, I chose U-G008 which is part of the USER-G group of patches. Press OK.
You should be in the "Play" tab. Press and select the "Audio In/Sampling" subtab. Now uncheck the "Use Global Setting". This will enable you to change both of the USB 1 and USB 2 column to "L/R" for the "Bus Select (IFX/Indiv) row only.
Next, press the "OSC/Pitch" tab (2 down from the Play tab), and the "OSC 1 Basic" subtab. In the Multisample/Wave sequence column, set everything i.e. 1-8 to "Off". This basically turns off all instruments because what we want is for the KONTAKT sample to come through and not the KRONOS sound.
Don't forget to save this program by clicking the top right down arrow, then select "Write Program".
The next thing you want after discovered this great feature, next thing is how to switch instruments via the Kronos keyboard. In other words, you don't want to go back to the MacBook to switch to a different instrument. Wouldn't it be great to be able to switch your Kontakt instruments via the Kronos keyboard? Here is how.
On the above, if you are able to create U-G008 (and tested that it works), go make U-G001 to U-G007 the same. Named the patches as "Kontakt" would be fine.
On the Kontakt side:
- click on the disk icon, in the drop down choose "New Instrument Bank"
- Next, click on the "spanner" icon on the top left and you should see a table of slots 000 to 128.
- In each slot, you can drag an instrument from the Library window from the left. In our example, you can do 8 instruments i.e. U-G001 to U-G008. So drag 8 instruments into 000 to 007.
- On the Kronos, go to program U-G001. On the Kontakt, click on instrument 000 that you assigned.
- Now all you have to do is on the Kronos either use the ^ or V to change program, or the wheel. As you do that, you will see the Kontakt instrument bank also move forward or backward. And you will notice the instrument is changed, playing through the Kronos L/R.