He friends,
with my notebook I am also using the 2nd monitor. My problem is that I unplug my notebook from monitor sometimes (when i go outside home with it). After I back home and I want to plug my monitor to notebook I have to again configure it in "Display - KDE Control Module".

I have chosen "save as default" -> apply but it doesn't make any difference. When i turn off notebook, unplug 2nd monitor, turn on notebook without plugged 2nd monitor, turn off notebook, turn on notebook with plugged 2nd monitor I have to configure it again anyway... it's really annoying!

How to make it to remember that when 2nd monitor is plugged (always) to use that config every time.

I put together a script for checking if an external monitor was plugged in, and if so, using it. But you'll have to run the script every time you hook up the monitor.
Whether or not there's a way to make it run automatically, I can't say.

Thanks!