Now the issue is about the openSUSE 11.4 Updates repo (priority 99). It shows newer packages version than the KR46 repos for some packages, therefore I’m not sure if I have to push Updates repo up in priorities or just forget its update messages an keep the KDE repos as first source.
You could check the package versions. I noticed that, for example, if you install a newer firefox version form the mozilla repo, updates will still show the update for the release version, but will install the update compatible with your version if it exists. This is easy to see when you update through Yast, in the versions tab.
Anyway, what works for me is this set of priorities: