int setDialogImage(string filename)
Returns non-zero if the function succeeds, zero if the function fails.
This function changes the image used in the filter dialog background. Under some conditions, e.g. STRETCHED dialog attribute, this could take some time to redraw - by using lockWindow(1) in front of the code and lockWindow(0) afterwards, the changes should only take a few milliseconds.
setDialogImage( "bitmaps\\myDialogBackground.bmp" );
Everyone can add his comments about his experiences with this function here. Tips for using it are welcome, too.