Slideshow won't advance past a certain photo but music plays on

I’ve been working many hours on a 21 minute slideshow with 335 photos and 7 songs; no problems until now. It gets stuck on a certain slide in the last song-the slide just sits there while the music plays on. Does anyone have experience with this problem? I have to show this slideshow to a large group of people in less than a week. Thanks in a advance for any help anyone can give me…

Version 3.8.8
Slideshow is 2.95 G. Many of the photos are pretty large.

This is fixed now, thanks to Josh at Boinx. Thank you, Josh!!

what was the fix?