Hi Chris,
The CMYK is not a Image::Magick problem it is a browser problem, last friday in our site we have same problems with bunch of pictures when we do little investigation why our web site won't show many of recently added images to our new product line.
We do various test on various browsers and the results was the same in Windows and Mac the pictures goes fine when uploaded to web the just don't show, so we pulled back all updates and resaved pictures in RGB mode and ... voila ... now everything works fine ;)
p.s. We do not use Image::Magick, all images are done by hand.
Cheers,
Boris
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