Well, this bug reminds me to this one. Everytime I run the application from launcher it doesn’t work when I have the OpenGL support activated, but when I run the application from a graphical console the most of times works correctly.
I had similar issues with the previous drivers in many applications in the same system, but with GNOME instead of KDE, specially made with GTK and when Krita crashes not show the crash report for KDE, so, I think that the error is not from KDE, Qt or Krita.
My computer has this features:
-Moterborad: Asus PK5.
-CPU: Intel Core 2 Quad Q8300.
-DDR2 667 RAM with 6 gigabytes of memory.
-GTX 650 as graphic board.
-openSuSE 13.1 as operating system.
-The kernel is 3.11.10-7-desktop.
-Xorg: X.Org X Server 184.108.40.2061 (1.14.4 RC 1).
-Desktop environment: KDE 4.11.5.
-Krita version: 2.8.0.
-nVidia driver version: 331.49.
This is a screencast made with Vokoscreen to show the error in action: