about colormanagement

[el Sismógrafo, S.L.]

>> proper CMYK support needs some form of color management,
>> so adding CMYK isn't exactly trivial.

>Maybe you can add some pointers about what "color management"
>actually is.

Color management tells you what to do with an RGB value which is out of CMYK 
gamut and tells you how to map RGB values to CMYK values and how to correct 
divergencies. The whole thing is relatively (!) easy as long as you deal with 
a desktop printer and a screen, as you can modify/adjust both output devices. 
As soon as you give your job away to a 3rd party, the only way to adjust 
devices is that both stick to common standards like Euroscale, etc. whose 
profiles are available to everyone in the form of icc profiles.

In fact, in some way or the other RGB => CMYK is always performed somewhere 
and somehow (mainly by printer firmware) and the only reason to implement 
cmyk in an application is to get control over color mapping. And this is only 
useful if you support common print standards, so if you want to do things 
right you must do that through icc support, otherwise all that effort 
wouldn't be worth a pair of fetid dingo kidneys.

There are still some more questions you have to get clear, eg how to deal with 
tiff, png, and jpeg that use rgb.