Forgive, if this question had been raised before. I have no time nor experience to search through such a huge forum for an elusive topic. My question is: where do programs store their window properties, such as layout of separators, height and all this stuff that is unrelated the proper data, such as the news feed sources? I would like to develop a mirroring solution that shares the proper data across all my machines, but omits the stuff that would brake settings tuned specifically for any of the computers. I mean, I can use huge Konsole window on my 24 inch screen, but then it wouldn't fit into my netbook screen. That is the kind of problems I am concerned about.

For KDE apps you can usually find everything in:
~/.kde{4}/share/config/APPNAMErc
and:
~/.kde{4}/share/apps/APPNAME/*

I think what you need is in the first one, the *rc file.

Most applications use a section in their *rc configuration file under ~/.kde4/share/config to store information like the window sizes, etc. This same configuration file is usually used to store the application configuration and preferences you have set as well.

Applications which deal with data (such as Akregator's caches of the RSS Feeds) will store those under ~/.kde4/share/apps/ in a folder named after the application.

Yes, thank you very much.