I tired to import virtualbox image of PLD linux, and extracted image of Windows XP Mode and in both cases I have similar problems. When I just following the guide, after:
qvm-create --property=virt_mode=hvm --property=memory=4096 --property=kernel='' --label red --standalone --root-move-from /home/user/win10-root.img win10
HVM just not see bootable drive. When I instead of that step create standalone from the GUI and copy root file system from raw image to root of the qube (dom0:/dev/mapper/<QUBE_ROOT_FS>) of matching System storage size it starts booting but crash or freeze later.