Ok, I went back to the solution you recommend. What I call "keyboard launcher" is a little icon in the top of my screen, where I can change keyboards. I think I enabled it in Keyboard Preferences. Maybe it's called "keyboard switcher" instead....
Anyway: OMFG... I just remember now, why I used the .bashrc-solution:
It *IS* more robust, because I use this java-program (I think it's built on java) a lot - which is called Matlab - and there are two cases:
1) Using my own advice with .bashrc (and "setxkbmap us -variant colemak")
2) Using your advice with keyboard switcher
Here's the result:
1) CTRL + "n" (n with the colemak layout) creates a new window just like it should. CTRL + "s" (s with the colemak layout) saves the file just as it should!
2) The above only works if I press CTRL + push the keys on the ASCII-layout! This is too stupid... I cannot remember to use ASCII-layout when I hold down CTRL and otherwise use Colemak-layout. But with "setxkbmap us -variant colemak" the CTRL key combination works flawlessly.
That's why I use "setxkbmap us -variant colemak" in my .bashrc and now I want to ask, how to automatically run this command: "setxkbmap us -variant colemak" after wakeup from suspend?
Try it out for yourself - I think Java don't like CTRL + Colemak with the fragile solution you seem to be using (this post explains why setxkbmap is more robust, from my point of view)...