Thanks for the reply.
Yes, I have tried all three boot modes.
Legacy
Dual
UEFI
None of these modes allows me to select the M.2 NVME drive. As I write this, could it be possible that I must select the UEFI, reboot, then try to select my drive. This might be an order of operations issue. I will got try that and see if it works.
Can you confirm that UEFI is the correct boot mode when using M.2 NVME as your boot device in the Mini XL+?
-scotts