'Display shadow behind slide image'- not working

[goddi]

I have some of my images panning/zooming in their respective Frames. I have added to all of the slides a white shadow behind the images, using the 'Display shadow behind slide image.' And, I have clicked on the 'Set for existing slides.'

However, I have noticed that for the several images that pan/zoom in their Frame, the shadow behind the image is black, not white. I can not seem to get these several images to match the rest of the images with the white shadow.

Is this a bug or am I doing something wrong???

Thanks... Gary