At least you got it sorted and if you could set a full screen
resolution then the graphics driver must be loaded. One other point
about the OSE version - it doesn't do USB so things like printers and
flash drives cannot be used ( apart from that it's fully functional ).

If you wish to have USB then you'd need to install the full Virtual
Box program from their web site. You'd have to remove the OSE version
first but you'd not lose the virtual OS's already installed - easy
enough to get them back when the full version is installed