I should add... If you update Brad Pitt's filmography, Twelve Monkey's will be added to it and he will be added to the end of the list of actors in the movie record. Unfortunately, updating the movie will remove him again, unless Merge filmography is selected in Preferences - Plugins. Using that option is fine, but then the credit lists tend to grow beyond the 15 main page limit and are not trimmed when the record is updated.
I think the behaviour of the program could be improved in two ways:
1. When a person is removed from a movie record (manually, or by running the plugin with the "main page only" option), it's usually because the user does not want to see them there—not because they aren't credited. Removing a person from a movie record should not result in the movie being removed from the person's filmography. In the rare case that's necessary, the filmography can be edited directly. I suppose both behaviours should be supported—some users may want to use the filmography feature to maintain lists of only movies that exist in the database. I suspect, however, most users would rather have complete filmographies (especially when movies in the database are highlighted anyway).
2. Selecting movie links in filmographies should not automatically add the person to the movie record. This is handy if that's what's wanted, but normally links are just for navigation—not making changes. It would be better if the "add to credits" function could be done with Alt-Click or something.