Question about grub in a virtual machine

[Chris Green]

I am trying to create a Virtualbox guest from a real physical Windows
10 image.

The initial problem is that the W10 image is from a machine that also
runs xubuntu Linux and thus the boot sequence is under grub control,
it's also an EFI machine.

So, I can get the W10 image off the machine OK and add it into
Virtualbox, however, since (I assume) it's not an actual 'boot it by
itself' W10 image it doesn't boot - I just get dropped into the
'grub> ' prompt.

At this point I'm a bit out of my depth but I managed to find some
information by searching and I did the following at the grub prompt:-

    insmod chain
    set root=(hd0,gpt1)
    chainloader /EFI/Microsoft/Boot/bootmgfw.efi
    boot

The Virtualbox image now boots and I get to the login but there's no
keyboard.  This *may* be a Virtualbox issue but it may also be
something to do with the above sequence I've entered into grub.  Is it
likely that the above is all that's needed or would one expect more?

Any/all sort of help would be most welcome.

    
-- 
Chris Green