I have just tried to boot from a cd burnt from http://cdimage.debian.org/cdimage/unofficial/efi-development/upload1/debian-wheezy-amd64-efi-test1.iso
I get the following message:
Welcome to GRUB!
Error: "Prefix" is not set.
The screen then clears and a pixel-ised blue screen is shown which is unreadable.
Looks like a corrupted GRUB Boot screen.
I have had this error with the Lenovo S205 with any GRUB2 distro except SUSE.
Many Thanks,
Roy Barnard