I prepared a new LiveCD of KDE4 which you can download at torrentbox.
This one required a few tweaks in the build system and many rebuilds, ugh. The unstable repository is well named ;).
How to build your own KDE4 Debian livecd
* Download the live-helper configuration from github
* Read Readme.live and make the necessary changes.
* Installing KDE in the livecd requires some script tricks. So, open the config/chroot_local-hooks/kde file and start adding at the end your custom commands
* e.g. apt-get install --yes anki
will add the Anki flashcard program to the Live CD. "--yes" is needed here to avoid apt-get to ask confirmation for every order.