You guys should check 2 things:
1. The problematic Gird Element is really perpendicular to the Section Line. If it is not it will not show, but if it is not and you check the "Show non-perpendicular Grid Elements" checkbox in the Grid Tool panel of the Section Settings Dialog, it will show up.
2. In the Grid Tool panel of the Section Settings Dialog there are the Show Grid Elements by Stories and the Show Grid Elements by Name fields. Make sure these are set to show all Grid Elements.
If neither of these solves it and the Grid Element is set to show in Section then it may be some kind of bug.
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