Forgive me for not knowing the intricate details of how it works, but I have had MythTV boxes running for a long time, since probably FC4 or FC5. The way I like running the frontend the best has been by invoking it through a .xsession file, which strictly turns the session into a mythfrontend session. Killing mythfrontend takes the machine back out to the login screen without ever showing the desktop.
I recently built out shiny new Fedora 7 machines everywhere and they just flat ignore my ~/.xsession file, no matter if I am running Gnome or KDE (which I am currently running). One day I got tired of it all and spent many hours hacking through until I figured out how to make it work again, but have misplaced my notes. Something in the yum repositories this week wiped it out (I am thinking kdebase?) and I can't figure out what I did.
Looking back through my history for vi sessions, I have played with /etc/X11/xinit/Xsession, /usr/bin/startkde and /etc/X11/gdm/gdm.conf though nothing obvious is showing up when I compare those files to a machine that I haven't yet updated this week.
As a quick hack, I stuck a script in ~/.kde/Autostart but that isn't working like I wanted since killing mythfrontend takes you back to the desktop and doesn't kill the session.
Does anyone even know what I am talking about? Thanks in advance.