I'm pretty sure that was the one I looked at, it was just too scary to be on that much of the cutting edge with a non-integrated solution. And the shipping was a killer. I saved a little money on the Seymour system but still very expensive. I'm only doing this once though. I know of no limit to masking ratios on my setup. I'm confident I won't have any trouble interfacing with C4, it will just need to be here to figure out. But it should be the same as any other masking system, and RS232 may be a likely candidate.