Trouble sharing slideshow with mov-files as standalone Player

Dear all,
I made myself a slideshow using Fotomagico 3.8.5 with pictures (pan and zoom) and some mov-files.
Exported as a Standalone Player to be displayed on any Mac, I found out that on a different computer my slideshow stucks when an mov-file has to start. The sound continues, but the pictures are not moving on.
I’ve checked the package content, the concerning mov-file is correctly exported.
Watching the same exported file on my own computer (on which the slideshow was made) is no problem, everything is working fine. But on another mac, it seems that only the mov-files cannot be seen.
What’s the problem, and how to avoid this?

Thanks in advance for anyone’s reply.
Best regards,

Please see thread