I am working on creating a slideshow for my upcoming wedding. The slideshow starts with a video and then transitions to photographs and audio. I spent a lot of effort to have certain photos sync with certain parts of songs, but after I save my project file as a video file I find the audio does not sync up correctly. Why it this? What can I do to resolve the issue?

Additional info:

The project file contains a video with audio embedded. Several dozens of pictures, and two audio tracks that are split.