Hi,
I am sorry to hear that you are having problems with your ppt. Just to have
a better understanding, what is the color for your scheme(if you are using
one)? Another thing you might consider too is to check if you are using slide
animations with other objects such as text boxes and buttons. Sometimes the
order of animated object might not be right(for instance, in your
presentation, the pictures might be covering the objects or text in your
slide).
The best thing you do is to give me a better understanding of your
presentation(if you are using animated objects, slide transitions, etc) that
way I can have a better understanding about your problem.
Thanks for your time and hope that helps,