D'oh!
Thanks for pointing that out. It's been a while since I've tried to use the Artist mix to control plug ins. Every time there's an update I check to see if it's any easier and it's alway very non-intuitive. If you open an EQ via the EQ button on the Artist Mix, the bands spill out low to high from left to right. If you open the same EQ via the insert button the bands spill out high to low from left to right.
Also, if you open an Eq via the insert button, and then click on the plugin with your mouse, the layout on the mix switches to the layout that you get with the EQ button.
It can be a bit frustrating.