1. sound. kdelibs-data wont upgrade (David Morley)

[Antonio Ricardo Correia]

I had trouble with that, but not only. Managing to run Kubuntu in my computer 
was impossible, it crashed at every login after the first install.
One of the problems I found was the one you mention. It warns that the 
previous version of the file is used by kdenetwork and won't allow the 
upgrade. It also deletes /etc/kderc that I suppose is needed by the Kubuntu 
version of KDE.
That said, I managed to solve the problem, in a radical way I confess, I 
decided to install Ubuntu and from there install the needed files to have 
Kubuntu (remember that Kubuntu is just Ubuntu with KDE instead of Gnome).

The process is very simple:

1 - Install Ubuntu.
2 - Run Synaptic, install kdelibs (last version) and upgrade all your 
packages.
3 - Go to http://www.ubuntuguide.org/ and follow the instructions on how to 
install Kubuntu from Ubuntu (it's really simple and straigthforward).

That's what I did and now the system is rock solid. I guess that many had the 
same problem with the install CD for Kubuntu 5.04 and just gave up installing 
it, and that is a shame because it's really a great system. It still has some 
glitches but minor ones that I suppose will go away with time.

Best of lucks,
Antonio