looks like UEFI bios cannot detect USB drive with zeroshell image (ZeroShell-3.5.0-USB.img.gz). There is no problem using old hardware, but modern UEFI in x86 mini-pc or even laptops make impossible to boot.
There aren’t any EFI-related components on the ISO image either. The only way this would boot on your EFI system was if it supported legacy BIOS boot.
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