None of the instances of that family are hosted by the reference line that is driving the rotation. Once you edit their workplane to be that reference line, they will rotate along with the rest of the conveyor.
Side comments: I recommend to simplify the family, and to do the rotation in another, next, family, rotating the whole conveyor as a single thing, to avoid issues like this, of smaller pieces being left behind, specially once the family is at work in a project. Some things seem to work in the family editor. The true test is in a project.
Alfredo Medina _________________________________________________________________ ______
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