The "Fall Apart" effect has a little visual glitch.
After the window falls apart, the small pieces of the window appear back on the screen and fall apart again.
Video demonstration: http://www.youtube.com/watch?v=8d3iz9rz0Sc
For sure time colliding with another close effect (fade or sth.) - ie. same thing as with minimize ./. magic lamp.
Please nevertheless attach the ouput of "qdbus org.kde.kwin /KWin supportInformation" (and of course try reproducing with disabled fade effect)
Created attachment 83522 [details]
KWin Support Information output
Yes, disabling the "Fade" effect resolves the issue.
I attached a txt file since KDE Paste says "Your paste triggered our spam filter and has been dropped" and doesn't allow me to put this.
*** This bug has been marked as a duplicate of bug 156484 ***
FYI: you can edit the fade effect (it's a script) in /usr/share/apps/kwin/effects/kwin4_effect_fade/contents/code/main.js and extend the fade(Out) time to 1000 (the duration of the fall apart effect) - it's just really long otherwise. (the 600ms present are already a "trick" to cover some other effect)
You may want to raise the curve shape to OutQuint to compensate the extension a bit more.