The layout anchor setting for an object -- say, a field -- may be different from the anchor setting for the group to which the object belongs. This can cause annoying and unexpected behaviors at time.
This is in FileMaker 16.
I can't make any sense of this behavior, and more important from a practical point of view, this behavior has repeatedly caused me problems that took time to diagnose (until I finally saw what's happening).
Thank you for your post.
If an object is grouped with different anchors, the top and left anchors will take precedence. Selecting the grouped object in the Layout Objects window will provide the anchor information. Make sure this is the same for all objects within that group.