If you know that you want KDE instead of Gnome, why not install the
KDE
Spin:
https://spins.fedoraproject.org/en/kde/ instead of installing a DE you
don't want, then adding the one you prefer later?
because the KDE live DVD does not work properly (stops doing anything
during minutes then respond for 1 seconds then sleeps again...) and
because after installation, I have a lot of troubles: after logout,
black screen, the new Plasma desktop does not have the possibility to
have small shortcut icons for the task bar... I guess that the KDE
spin is not prepared as well as the Gnome one. So I will give a new
try to Gnome.
Frédéric