This Live System image failed to boot

typo?

This is a copy/paste of my pre 11/26/2020 /etc/grub.d/40_custom

#!/bin/sh
exec tail -n +3 $0
# This file provides an easy way to add custom menu entries.  Simply type the
# menu entries you want to add after this comment.  Be careful not to change
# the 'exec tail' line above.
menuentry "CloneZilla ISO" {
  # The string between " and " below is the actual name of the ISO file you just do>
  # and copied to the /opt directory (where optional software resides) and is the c>
  # version as of the last edit to this [HowTo].
  set ISOFile="/opt/clonezilla-live-20201102-groovy-amd64.iso"
  loopback loop ($root)$ISOFile
  linux (loop)/live/vmlinuz boot=live components config findiso=$ISOFile ip=frommedia toram=filesystem.squashfs union=overlay
  initrd (loop)/live/initrd.img
}

You downloaded the .zip file instead of the .iso file

I just checked again what’s in my /opt/ and I have:
clonezilla-live-20201102-groovy-amd64.iso
clonezilla-live-2.7.0-10-amd64.iso

My boot partition is encrypted with LUKS. My /opt/ directory is in my boot drive. I enter my LUKS password at boot, hold shift to bring up the grub menu, and then select CloneZilla ISO to be booted.
Is it possible that my LUKS encrypted boot drive might be preventing me from using the CloneZilla isos in /opt/ even though they should be decrypted at boot?

but you could do the same and report back in parallel

Now a copy/paste of my current /etc/grub.d/40_custom is:

#!/bin/sh
exec tail -n +3 $0
# This file provides an easy way to add custom menu entries.  Simply type the
# menu entries you want to add after this comment.  Be careful not to change
# the 'exec tail' line above.
menuentry "CloneZilla ISO" {
  # The string between " and " below is the actual name of the ISO file you just downloaded
  # and copied to the /opt directory (where optional software resides) and is the current
  # version as of the last edit to this [HowTo].
  set ISOFile="/opt/clonezilla-live-2.7.0-10-amd64.iso"
  loopback loop ($root)$ISOFile
  linux /live-hd/vmlinuz boot=live union=overlay username=user config components quiet noswap nolocales edd=on nomodeset ocs_live_run=\"ocs-live-general\" ocs_live_extra_param=\"\" keyboard-layouts= ocs_live_batch=\"no\" locales= vga=788 ip=frommedia nosplash live-media-path=/live-hd bootfrom=/dev/sda4 toram=live,syslinux,EFI
  initrd /live-hd/initrd.img
}

Ran sudo update-grub:

Generating grub configuration file ...
Found theme: /usr/share/grub/themes/manjaro/theme.txt
Found linux image: /boot/vmlinuz-5.4-x86_64
Found initrd image: /boot/amd-ucode.img /boot/initramfs-5.4-x86_64.img
Found initrd fallback image: /boot/initramfs-5.4-x86_64-fallback.img
Adding boot menu entry for UEFI Firmware Settings ...
Found memtest86+ image: /boot/memtest86+/memtest.bin
done

Rebooted and selected CloneZilla ISO from the grub menu and I got:

error: file '/live-hd/vmlinuz' not found.
error: you need to load the kernel first.

Press any key to continue..

Then I get sent back to the grub menu.