Animations out of sync

I'm trying to update a course created with Articulate Presenter 9 and Powerpoint 2003. The content and animations are fine, except when I need to edit them. When I go into Sync Animations, the first animation launches immediately when I begin the sync process. In addition, an additional animation appears on my list, which generates an error.

I've tried removing all the animations and re-assigning them, with the same result after the reassignment. I have also tried both copying the slide and creating a new slide and re-creating the content with the same result.

Any ideas how I can salvage this course?