cp new-checkn1x.sfs /tmp/checkn1x/boot/checkn1x.sfs
xorriso -as mkisofs -o better-checkn1x.iso -isohybrid-mbr /usr/lib/ISOHYBRID/MBR.bin -c isolinux/boot.cat -b isolinux/isolinux.bin -no-emul-boot -boot-load-size 4 -boot-info-table /tmp/checkn1x
Result: A custom ISO with updated tools, optional persistence, and faster boot—your own "better" Checkn1x106amd64iso.
Instead of a black screen, a better Checkn1x shows verbose output, lets you toggle verbose boot with a keypress, and saves logs to the USB drive. checkn1x106amd64iso better
The ISO uses SquashFS. Locate the .sfs file (usually checkn1x.sfs): cp new-checkn1x
unsquashfs /tmp/checkn1x/boot/checkn1x.sfs
cd squashfs-root