There is a older version 1.2 that will also install a plugin for use with Gimp. It is a python plugin so if you use linux you do need a working python.
A bit about it here: https://www.gimp-forum.net/Thread-CMYK-c...0#pid16030
edit : I wonder what happened to the version 2 ? Looking at the code version 3 is now in development.
A bit about it here: https://www.gimp-forum.net/Thread-CMYK-c...0#pid16030
edit : I wonder what happened to the version 2 ? Looking at the code version 3 is now in development.