Starting Rocks'n'Diamonds when redshift program is running causes R'n'D to crash.

[filbo]

If the above does work, it sounds like too much trouble to get working.

Problem solved by deleting Kwin config files in ~/.config and /.local/share and a reconfiguration afterwards.

Hmmm, sounds like just 'save and delete the relevant files in ~/.config and ~/.local/share; log in to KDE and see if the problem persists; put the files back'. With difficult details (1) what are 'the relevant files' and (2) need to carefully do the file manipulation while *NOT* logged in via KDE; e.g. on text console login (Ctrl+Alt+Fn, value of n varies on different distros -- there should be around 4-6 different text consoles available).

But that's actually the wrong approach. Right approach:

1. create a new test user
2. login with that user under KDE (X11)
3. test RnD (works)
4. configure `redshift` or `gammastep`
5. test RnD
6. if it still works, there's some difference between this 'blank' KDE setup and whatever your regular account has, figure out what it is...