Version:           0.39 (using KDE KDE 3.5.3)
Installed from:    SuSE RPMs
OS:                Linux

I get no backtrace so this is what happens as I see it happen (there are two parts the report):

Part I:

I open superKaramba (sK) and load some widgets (just three at this point, system_monitor_crystalclear, miloCalendar 0.6, and LiquidWeather ++ [v13.1.1]).  If I use kwrite to open, say, the system_monitor_crystalclear.theme file to modify the location of the theme's parts, sK will immediate crash with no error (and no KDE crash/backtrace dialog).  The widgets cease functioning and no keyboard/mouse events work on the widgets or the taskbar icon.  I must force quit (kill -9) the running sK process from a terminal/ksysguard.  

Part II:

When I do this, the list of available widgets in the sK Themes dialog is now erroneous--it shows some but not all of the installed themes (e.g., the ~/.kde/share/config/superkarambarc file [KNewStuffNames] section shows themes that are not listed in the dialog and I can go to ~/.kde/share/apps/superkaramba/themes and see themes that do no show up in the dialog).  To get the theme list back to normal, I have to hand edit the superkarambarc file and delete the list of installed themes, then go to the Theme dialog and reinstall each of the themes manually.

NOTE: sK runs normally when I restart it after the crash and the themes it does show do run and I can use the local theme option to go find the themes that are in the ~/.kde/share/apps/superkaramba/themes directory and load them that way.