It's a bit unclear. Between the cartridge port and the A/V connector you should have access to the signals you need to make it work. If I had to guess, the fact

It's a bit unclear. Between the cartridge port and the A/V connector you should have access to the signals you need to make it work. If I had to guess, the fact that CSYNC reverses direction is kind of awkward for a device that needs to act as a transparent pass-through for non-32X games.