It is now available at:
CMYK Shader (http://www.ruimac.com/c4dplugs/)
Hope all you guys doing print work find it useful. It is not too expensive, I believe (10 Euro). Sorry but I had to charge something for it as it was a major mathematical chalange and took me a deep investigation in the net, lots of trigonometrical calculations, many tests and coding.
It was one of those projects that makes us feel so gratifying when we see it finaly working :-)
Check it out and tell me what you think, even if you don't buy it ;-)