FYI, the game works on xp using virtualbox 3.2.8. There is just one catch: you need to install the guest additions (d3d) in safe mode - this is documented somewhere but can't find it anymore.
IIRC, I did like this: install the trial version, including slimdx and directx9. The game won't start, but boot in safe mode, install guest additions, boot normally and then it will work. I may be wrong with the ordering of things, debugging windows problems is always "throw random stuff at it and see what happens" for me.
It did crash once, but is otherwise playable (spent some good hours on the tutorial campain). Nice game.