Jerky output on slideshow

I am just finishing up a 21 minute slideshow for a presentation in a theatre to several hundred people. My test runs of the show have some very jerky animations. Most slides the animations are kept to a minimum Ken Burns effect but on a few of them I have some more dramatic zooms and pans.

These zooms and pans are not acceptable for presentation as they skip and stutter. Is there an optimum setting for these types of program features or will they not work at all.

What system configuration you are running on? MacOS version? Hardware? FotoMagico version?

I am running an iMac with 3.4Ghz processor, 8G of RAM, 2 TB of storage with 1.5 available.
Latest OS just updated a few weeks ago.

Fotomagico 4.31

21 minute slideshow, with 246 images.