As I am way to curious I give it a try and manage to have a build of the latest kernel 18.104.22.168 booting.
But, as there is always one, the issue is not in the modules and the need to rewrite the linuxrc file but rather within the initrd image.
Indeed, Fulvio has put some modules directly in the initrd image for loop devices and USB/SATA drivers -> need to create a new initrd image as well.
So I did and result is OK.
OK this means we can do it but we really need to find a way for several users to simultaneously be able to bring updates or upgrades to Zeroshell without disk image, the first partition is not a problem on CF card though. But as you can see links are everywhere: initrd, rootfs, Z iso image.
Fulvio, as everything is your great work, what would you suggest?