Oh, assumed it was software cause he had posted this of the game running windowed without needing to be flipped by hardware. alamone.net/image/Clipboard03.jpgNot sure if that's just the nature of forcing it to run in a window and fullscreen will always be flipped.That was alamone, and he was using the same external hardware processors linked in the Japanese guide to flip the image to the correct orientation. He didn't modify the software.I remember someone having a cabless setup in norcal for DBEX and I think they modified the game to flip the image, no external hardware at least. I sadly don't remember who it was, just that they lived in San Jose. I do remember them selling the setup on eBay several years ago though.
So that is likely the Pc version modfied, to re-enable coins.
As i already stated however you can directly modify the game to fix the screen rotation.