Hi @Citadel-North,
Thanks for reporting!
We have a couple of reports of the issue with booting on Raspberry Pi 4. The bootloader packages of Raspberry Pi OS were changed, and now there can appear some challenges with the correct booting. But our devs have found how to fix that, and we’re currently on the testing stage. Once the updated image is out, I’ll let you know.
There’s a workaround suggested by one of our users which you may try. But I’ve not tested this myself, so I can’t guarantee it’ll work.