Hi,
First time i used the aarch64 version for a CM3 i wasn't able to boot cause the "/dtbs/broadcom/bcm2837-rpi-cm3.dtb" file was missing. I took the other existing one ending with ...-cm3-io3.dtb and renamed it.
I guess the dtb-file is missing? What is the use case of the "io3" dtb-file?