I have the same problem. My File is about 300 mb but I cań’t export it to mobile o iPad device.
Using the Search function in this forum I found this -http://forum.bolidesoft.com/viewtopic.php?f=2&t=2409&p=9131#p9131
The developers website contains this valuable information:https://www.bolidesoft.com/allmymovies/iphone.html
Apparently, the apps are just an extension of the computer maintained database, built for reference only. A handy pocket reference of the movies you have entered into your database. (AllMyMovies for iPad requires an additional purchase and license.)
If you already have both programs, could you elaborate on how you are attempting your transfer?