I've read posts where they say you should start with Fedora is you want a desktop type of Myth install. However, now that I've invested alot of time in KnoppMyth (and it's almost working), it seems more logical to apt-get the packages one wants and customize the install.

Anyone have luck doing this?

i have installed kde on a fresh install of R5E50.
apt-get update
apt-get install kde kde-extras

to get rid of the existing gui also:
dpkg --purge fluxbox

on reboot you will enter the kde environment.

please note that mythtv will not start automatically.
to get it to start, from a terminal type "mythfrontend",
or just edit the kde startup file.

i have also installed openoffice
apt-get install openoffice.org

and finally, ii have successfully preformed an apt-get upgrade (yes UPGRADE)
all works flawlessly...

I followed your suggestion, thanks, I like the KDE desktop much better.

I also purged fluxbox, but the exit menu (I think it's Knoppix) is really a hasstle. It's the one with three round buttons at the bottom and when you try to log out (note that you've already logged out of KDE by this time), it ask for an administrative log out.