Actually, this may be possible using a similar fudge to the current method where we replace the movie file before creating the DVD.
If we ensure our images are all named the same, we can create a picture compilation from the folder of photos normally included as the extras folder on the DVD. These photos are replaced when we process a new customer so the picture compilation will pick up the new images when it renders the DVD. There will be an issue with media offline if we don't have enough photos. It needs further investigation.