With the image downloaded from http://download.grml.org/grml64-full_2014.03.iso I 
cannot run a memtest on my mac.

When choosing the option from the boot menu, I get the error that the file linux16.img 
is missing.

Steps to reproduce:
* Boot the grml image
* choose Addons > Memory Test (memtest86+)
* Get the error message:
error: file `/boot/grub/x86_64-efi/linux16.mod' not found.
error: can't find command `linux16'

Looking at the folder /boot/grub/x86_64-efi/ from the grub command line reveals that 
there is only a file 'linux.mod' and 'linuxefi.mod'

Since I don't know grub enough to replicate what the menu does, thats where I have to 
stop for now.

What I would expect: the memtest should run. :)