Version: Revision 755041 (using KDE Devel) Installed from: Compiled sources The background selector doesn't update preview with the "select wallpaper" dialog. Step to reproduce: 1) open "configure desktop" (RMB on desktop) 2) click to the "browse" icon 3) select an image from the dialog and click "open" 4) The "Picture" field is updated but the preview is not. clicking OK/Apply will correctly set the selected image.
There's been no updates to the relevant source since rev 755041 but this is working for me fine here. Does the problem happen with any image for you? If not, are there any differentiating attributes of the ones that don't - eg, type, size..? It might also be an issue with some other component that has been fixed in the mean time so could you try with latest subversion again, please?
Should be fixed with r757616.