A large presentation consisting of many individual images becomes "costly" in uploading fees.
My solution to this problem is to upload your images to a webhost (preferably a free host account)and use the llParcelMediaCommandList()function to load the images onto the PrimFace, since BMP, GIF, TGA, and JPEG file formats are supported.
In effect, this becomes a frame-by-frame "movie" if you will, however with its own drawbacks, such as the 2.0 second delay for the function, the need for a more advanced script, as well as any other problems that may arise.
But, as an alternative to paying $L10 for each upload, it has served me well thus far.
I have SUCCESSFULLY used this method in teaching my Basic Scripting classes in the past, and due to the fact that my "script-images" change so frequently, it has become a more economical, albeit less-efficient, method.