How can I properly add an entry in the grub to boot from an ISO file?

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Hi, I'm trying to boot Live Raizo from an ISO file in Fedora 28, I tried to add an entry from Grub Customizer but when I reboot the system and try to start Raizo, it says linux and initrd commands could not be found (as in this picture: https://drive.google.com/open?id=18NA...).

The entry looks like follows: https://drive.google.com/open?id=1clY...

I hope somebody can help me, thanks in advance.