@MarkTime - speed
VirtualBox works entremly well if you have virtualization in CPU and it works extremly poor without it. I have Phenom II 550 and AROS runs at "native" speed under VirtualBox there.
Yeah, that's quite likely to be the biggest problem.
@MarkTime:
A solution worth trying: Install the files into a directory instead, and download the Linux-hosted version of AROS, copy boot/aros-unix into the boot directory under where you put the files, and start that instead. That's what I've done with my Icaros setup, since the CPU on my laptop doesn't support hardware virtualization.