Sparky won't install iso created with Sparky backup

[jnwright]

I created a backup .iso file of my Sparky 8.0 system.
Then I used the USB Imager app to burn the .iso file
to a USB.
Then I tried to install it to a newly created ext4 partition.
It looks like the installation is going to complete but at
the last it displays a black screen with the message:

[0.073297] x86/cpu: SGX disabled or unsupported by BIOS.

BusyBox v1.37.0 (Debian 1:1.37.0-6+b3) built-in shell (ash)
Enter 'help' for a list of built-in commands.

(initramfs)