Accessing faders in a Kontakt plug-in using GarageBand

JudyK

I have the Hearth & Hollow vocals plug-in from SpitfireAudio and the free version of Kontakt. I have a Korg MicroKey Air keyboard and I use GarageBand on my Mac. Hearth & Hollow has a fader to adjust the vowels. I'd like to be able to adjust it as I record or, at least, afterwards to have the vowels change during one phrase. The Hearth & Hollow demo video shows this being done with a physical fader.

When I turn on automation in GarageBand I see a number of controls but none of them control the vowels. I also see some 2000 possible settings under Kontakt 7 but trying out a few of them it only seems to control the volume.

Anyone know how to do this or if it's even possible? Or is it time to upgrade to Logic?