Ok, so we have a few bumps with 4.6 KDE and we are working hard to resolve them as soon as possible.
An issue with the skel file is black text on black background, this is fixed in app-misc/sabayon-skel-5.5-r2, but the problem is, we don't touch your home folder, so you need to manually do this
That will pull the new fixes, but here is what you need to do next
as USER, not root, from konsole:
cp -a /etc/skel/.kde* ~/
and than restart KDE
This will copy the default Sabayon skel files to your home directory and reset your KDE and things will be all pretty again
Issues with magneto, multiple instances. We are aware of this and working on it. For now, can uninstall it or just right click on the extra ones and choose exit.
System-Settings - Startup and Shutdown - Session Management and check the Start with an empty session click apply and logout and than log back in, I only get one magneto