I had seen that tails had 32 bit efi, so I tried booting it. The usb was bootable (laptop booted from it) but the tablet did not boot from it. I'll have to do some more research on what's the difference between the net install boot process and the live cds (debian, ubuntu and tails all fail)
FWIW here's Tails' implementation for live-build 2.x, using GRUB2's
support for reading syslinux configuration:
Depending on what exactly you need to support from the syslinux
config, you might need a fairly recent GRUB2.