I am making a presentation to upload on YouTube, and for that I will have it timed with an audio narration. I have gone through the slides and, using SlideShow>Rehearse timing, have assigned a time for each slide to stay on the screen. Unfortunately, the timing doesn't hold. When I exit that software and save it, them go back in, when I go back I find that the timing didn't hold. There is still a time designated for each slide on the screen (in "multiple slide mode," I don't know if that's what its called), but it is not what I put in there. What am I doing wrong?