Joker,
Win32 Disk Imager did not work for me either. If you have access to a Linux box you can use the supported method of dd. If you don't you can use the UNSUPPORTED method of unetbootin. Just be sure to edit the syslinux.cfg like my other post says. I realize you are going to EFI boot the machine but fix syslinux.cfg just in case.
