Initially I had P4 in the command and DWC kept crashing. For a test, I have added just the A4 to the M584 command to see how it goes. Again DWC crashed, even if the extra axis were hidden. So, based on that, I think the DWC is making the controller unusable in this scenario. For all other issues, consider the other related thread.

If that breaks anything, put the DWC files from github back on the card.

New thread that re-summarizes a ton of things about CNC coordinates here:

https://www.duet3d.com/forum/thread.php?pid=42850

@cmefryday:

I'm working with- Fusion360 and a Shapeoko 3 CNC router, wishing i could use my Duet.

Can you tell me which Gcodes not supported by the Duet are preventing you from using it for CNC?

I created a thread in the firmware wishlist section of the forum about adding G2/G3:
https://www.duet3d.com/forum/thread.php?id=755