Relationships, network sharing, and global fields
Sorry if this is a known design parameter, but I just went around the block a few times trying to figure it out so figured I'd post. This comment helped me troubleshoot it http://forums.filemaker.com/posts/b5aaa4e51e?commentId=41127#41127
Problem was that related records more than one relationship away, with a relationship established via a global field, would show up in a portal for a machine opening the file locally, but would not show up for machines accessing the file via sharing. Seems the issue is with global fields defining relationships.
I was able to make the related records show up on a client via sharing by changing the relationship to be one table away, even with a relationship defined by a global field. Or I could make the related records more than one relationship away show up on the client by making sure no relationship defining fields were global fields.
Perhaps the client isn't aware of global field values more than one table distant?