Power on the MOXF8
Connect the Main L&R Output to two channels of your Audio Interface.
Connect the 5-pin MIDI Out to the MIDI In on your MIDI interface, and a MIDI Out of that device to the MIDI In of the MODX.

In the MOXF
Press [UTILTY]
Press [F6] MIDI
Press [SF4] OTHER
Set MIDI I/O = MIDI

For your other devices consult their documentation. Since you are not using the MOXF as your audio/MIDI interface, you need to follow the recommendations for your chosen devices. The MOXF8 will be referred to as 2 inputs of your Audio Interface, and as a MIDI In/Out on that same device.

What you miss out on by not using the MOXF via USB for MIDI, is the ability to use the Yamaha MOXF6/MOXF8 Editor Stand-alone (requires USB connection). And using the MOXF as Control surface.
What you miss by not using the MOXF via USB for Audio is the ability to have dual stereo record Outputs.

Since you have a control,surface, and an audio interface, you miss nothing there (except the second MOXF stereo out). You may want to connect the MOXF via USB for MIDI communication — (if you have an extra USB port on the computer). You can use just the MIDI portion of the Yamaha Steinberg USB Driver. The Editor helps organize your MOXF setups per session, it can be run along side your DAW or as a plugin if your DAW is VST3 compatible.

Hope that helps.

Both X-Touch and MOXF integrate perfectly with Cubase (provided). MOXF integration with Cubase is particularly stellar - and the main reason I keep delaying upgrading to Montage, which doesn't seem to have control templates or ways to name their functions (hopefully someone can prove me wrong).

That said, they will both work well with any DAW - in case Cubase is not your cup of tea. Congratulations on your purchase!

MOXF integration with Cubase is particularly stellar - and the main reason I keep delaying upgrading to Montage, which doesn't seem to have control templates or ways to name their functions (hopefully someone can prove me wrong).

Not sure what you’re looking (or waiting) for, DAW Remote Mode was added to MONTAGE quite some time ago, in OS v2.5 (templates for Cubase, Pro Tools, Logic Pro, Ableton Live)

But upgrade to the MONTAGE because it’s ten times the synth that MOXF is, not for the remote control features alone.

I was referring to the [50] control templates which can be created with the Remote Editor - I often find myself working on several projects at the same time and having those parameters labeled on screen and organized is very useful.

I will be updating soon regardless, initially the lack of a sequencer (recently added), channel midi allocation (partially addressed) and the above limitation were important enough for me to put it on hold as I currently use them in almost every session - my growing studio is in greater need of a nimble workflow than extra sounds at the moment. The montage connect sync does seem to be faster and easier to manage from what I can tell, and the updates are very encouraging - I commend Yamaha for listening.