Deploying Big Sur 15.1 volumes unmount then it stops

I’m a first time user of MDS but have managed to get things configured correctly (I believe) including fixing the clash between Profile Manager and MDS. However I’m struggling deploying my first image using either the hdiutil mount http://x.x.x.x:8088/file.dmg method or from a USB drive.

The image mounts fine from Terminal and I can execute the Run command. The script starts as I can see some text appear, it then says it successfully unmounted all volumes… and stops. Nothing else happens at all. Should I see something happening? What am I missing?

Thought I’d cracked it. I noticed that on the guidance video on the website, they are showing adding the Install file (obviously I’m using Big Sur), but I had been pointing the system at the freshly downloaded .dmg file! So I extracted the .app and tried it all again. No joy :frowning: Attached is a photo of what I see. Open to suggestions, the Mac mini has an Apple M1 chip if that helps?

The issue is the boot environment is 11.0. Apple didn’t allow 3rd party utilities to run on M1’s until 11.2.