Profile photo of TJCornish

DCAs are different than groups they affect not only the fader level, but anything that is post fader as well, such as post fade auxes.

For your second to last point – this is probably what you’re seeing. Your auxes are set to post fader mode, which means changes in the main level affect them. This is desirable for things like effects. For use as monitors, set them to pre fader.

As far as I know, you can assign the effects return to a fader.