I have this strange issue on my laptop with KDE 4.5 on Kubuntu. If I attach a second monitor that does a higher resolution than my main laptop screen and the k-bar ends up on that screen, it thinks the maximum width of the k-bar is still limited to the size of my other screen. This used to work fine on KDE 4.4. In addition to this issue, making the k-bar 1920 wide makes the k-menu extremely wide as well, which also wasn't an issue in 4.4. Anyone else noticed these things?

Also, is the Display manager ever going to get an option to select which screen is the "main" screen and will end up with the k-bar and such?

Also, is the Display manager ever going to get "profiles" for attached monitors where it grabs the EDID and decides if there is a predefined setting that matches that EDID and loads it as soon as it is plugged in?

This is definitely a bug and regression in KDE 4.5. Please file a regression bug report at bugs.kde.org.

As far as I am aware, features to load different settings depending on the present monitors have not been requested yet.

With regards to changing the Primary monitor, simply pass the "--primary" argument to xrandr.

Example: xrandr --output LVDS --primary