Is CamillaDSP my only solution? Active Xovers: MacOS -> HDMI -> AVR

Hey Folks,
I've got a nice few generations old AVR here that accepts HDMI, a older intel Macbook Pro with HDMI out & a dream.

I'd like to play with making some upcoming projects active or at least just having a fiddle in that space and I was thinking I'm one software implementation away from being able to "test the waters" and make some active xovers + dsp via the 9 channels of amplification onboard the AVR.

Is CamillaDSP the only solution I have for creating crossovers and dsp, assigned to individual surround channels via HDMI out?
Is it a solution to do what I'm thinking at all?
I think I'd need to use PCM mode?
Is there an easy to use graphical UI for camilladsp that allows you to do this?

I'm not sure what terminology I should be searching within the forum to even research this on my own. I'd appreciate any pointers.

Cheers!