To change GTK themes under KDE4: 1) Install 3 packages from the repository (using synaptic): A) gtk-kde4 B) kde4-style-qtcurve C) qtcurve-gtk2 Gtk-Oxygen-Molecule will be removed during the installation. 2) Reboot the computer (or just log out and back in) 3) After the reboot go to
Kmenu > More Applications > Configuration > Configure Your Desktopor as alternate route press [ALT] + [F2] keyboard combo and type in systemsettings and press [ENTER]
I recommend using the QtCurve theme. It works PERFECT and looks great.
Changes will be applied to the GTK applications after they were closed and reopened.
Hope this helps.