Leszek Trenkner (Yahoo!, Panasonic forum, 24 May 2004)...
If I release shutter immediately after the shot (before `auto review' function starts, when the camera is writing picture to the memory card), the function works...
But if I hold shutter some 0.5 second longer (and release it when auto-preview image is already shown) the preview is canceled. With longer shutter times I tend to {hold down the shutter-release, thereby operating the camera gently to give OIS (optical image stabilization) a chance}and so I came to my previous conclusion.
You just shouldn't move shutter button during auto preview image is shown. I guess it has nothing to do with firmware...