several months ago, I started a project to make the Komplete Kontrol MK2 controllers by Native Instruments usable on Linux, which is now finally hosted on Github.
Link
With the software, you may
* split the keyboard in various zones with different MIDI channels and lightguide LED colors
* configure the MIDI parameters send by all the knobs, buttons and sliders
* create various preset files and toggle them using the preset buttons
* watch for values and other information on the two LCD displays
* remote-control Bitwig Studio if the OSC plugin by Moss is installed in Bitwig
For a link to the project website look at the beginning of this posting! If you are looking for an installable Ubuntu package, look at the Release page there!