I got it solved thanks to Hans in the KDE forums here:
http://forum.kde.org/viewtopic.php?f=66&t=96693It should be possible to achieve what you want in System Settings -> Common Appearance and Behavior -> Shortcuts and Gestures -> Custom Shortcuts -> Edit -> New -> Global Shortcut -> Send Keyboard Input. Select a trigger, click on Action and write e.g. Home, End, PgDown etc.
-SS.