Done that. Wonderful! Less options look better. No issue at reflashing. But I had to install libftdi1.
Edited the USB option to (usb0,gpt1)/syslinux/syslinux.cfg I get error: file '/boot/grub/i386-coreboot/true.mod' twiceChoosing the last option (the "cat" module) generates also errors about sfs.mod and affs.mod.