To change the window manager is very similar if not the same as in KDE3. The major step is to export KDEWM=”your-window-manager” General instructions can be found at http://developer.kde.org/~seli/kdewm/
But instead of doing the exporting in ~/.profile as mentioned in that article you should put it in ~/.kde/env/*.sh so for example you could name your file kdewm.sh and make it’s path ~/.kde/env/kdewm.sh
Unfortunately it does not work straight off the bat with the Awesome window manager. Does anyone know how to get it working?