For what it's worth, it's not entirely unheard of for early versions of DirectDraw to have exports/interfaces that are simply unimplemented. It also looks that when these were originally implemented in 2012 (commit f018a861377edb96fecc7df644e04b0e9499897e), the main purpose was to introduce the various IDirect3DRMDevice stubs, and not so much CreateDevice() itself.