Does not the following work for you?
su -
root PW
konqueror -profile filemanagement
worked for me in 2009. It is of course for the file manager mode, you would have to change that for whatever mode you want.
I am going to reinstall, this time like AussieJohn, installing Gnome, and then install KDE3, KDE4 is a bit of a mess, and a lot of stuff just doesn't work, or work correctly with it. But more then likely I am going to go to Debian SID, or LinuxMint KDE CE, but I will give 2009 one more go