Exactly. They also have to design the specific fitment, adapting the CSRV tech to the appropriate bottom ends. Numbers of cylinders, displacement, etc have to be specifically accounted for.
Sometimes the same head can fit a (somewhat)range of displacement, because stroke may be longer although the bore stays the same. I am curious though if timing functions in essentially the same manner, as far as advance/retard of intake/exhaust "cams"/rotary valves... I assume the rotary valves have individual adjustable gears?