There is a version of the demo (11/9/2008 or later) that looks almost identical to the Genesis version, with some good horizontal parallax. But getting a smooth-running game with vertical parallax, with the sparkly ocean & trees in the background, moving at a different rate from the entire foreground, is too much to ask from the PCE, IMO. For two layers of scrolling/warping backgrounds, plus sprites, really a single-background VDP like the PCE's doesn't suffice.