Is there anything special to do to make the USB ports work? I can’t get any USB stick (i.e. neither my Z-Wave stick nor a storage device) recognized by the kernel.
Solution: I had to edit config.txt on the HAOS boot partition to add dtoverlay=dwc2,dr_mode=host to the [pi4] section. Everything works fine now. Apparently, the CM4 disables its USB ports by default to conserve power.
Postscript: So of course I got the wrong image (i.e. the generic RPi4 one). Any way to flash the Yellow specific image from the command line or do I need to extract the NVME drive again?