legacy-bios and uefi boot usb stick

[John Frankish]

I've made a couple of dual legacy-bios/uefi boot usb sticks using grub-2.00.

Both of the usb sticks will uefi boot linux, but there appears to be a problem 
with legacy-bios boot of linux.

One of the usb sticks gives an "invalid partition table!" error and the other 
will boot, but an error message scrolls past too quickly to read just before 
the grub menu is displayed.

I've left more than 1mb before the first partition for the mbr and grub files - 
is this perhaps not enough or is there a different problem?

Details below

----------

$ fdisk -l /dev/sdb

Disk /dev/sdb: 62.2 GB, 62209916928 bytes
118 heads, 22 sectors/track, 46804 cylinders
Units = cylinders of 2596 * 512 = 1329152 bytes

   Device Boot      Start         End      Blocks  Id System
/dev/sdb1               2       46000    59706702  83 Linux
/dev/sdb2           46001       46804     1043592  ef EFI (FAT-12/16/32)

$ file -s /dev/sdb
/dev/sdb: DOS/MBR boot sector

$ dd bs=512 count=1 if=/dev/sdb 2>/dev/null | strings | grep GRUB
GRUB

$ sudo mkfs.ext4 /dev/sdb1
$ sudo mkfs.vfat /dev/sdb2

$ sudo mount /dev/sdb1
$ sudo mount /dev/sdb2
$ sudo grub-install --target=x86_64-efi --boot-directory=/mnt/sdc2/EFI/BOOT 
--efi-directory=/mnt/sdb2 --removable
$ sudo grub-install --target=i386-pc --boot-directory=/mnt/sdb2/EFI/BOOT 
/dev/sdb

$ cat /mnt/sdb2/EFI/BOOT/grub/grub.cfg
loadfont unicode
insmod efi_gop
set gfxmode=1366x768x32
set gfxpayload=keep
set gfxterm_font=unicode
terminal_output gfxterm

search --no-floppy --fs-uuid --set=root d4432cde-d21a-4d40-b44b-f097ce72cdba

menuentry "core" {
linux /boot/vmlinuz quiet text tce=UUID="d4432cde-d21a-4d40-b44b-f097ce72cdba" 
waitusb=10:UUID="d4432cde-d21a-4d40-b44b-f097ce72cdba"
initrd /boot/rootfs.gz /boot/modules.gz
}