I found an interesting case where you can have a Beam apparently disappearing from the Floor Plan although the Home Story is set correctly and the Show On Stories/Floor Plan Display/Show Projection fields are all set correctly.
It happens only under special circumstances but still it is good to know.
If you uncheck the Show Center Line checkbox in the Floor Plan and Section panel of the Beam Settings Dialog then only the Beam contours will be shown.
Now if you switch to another View at this point then you can find the Beam is not displayed in the Floor Plan Viewpoint - it looks like it disappeared. You may think its Layer was turned of by the activated View, but it is not the case.
The cause is the Beam setting stored in the Model View Option combination stored with the activated View. If the "Show Beam as" field was set to "Reference Line" in the Mode View Option combination, then it is supposed to show only the Center Line of the Beam, but that is turned off in the Settings Dialog so nothing is shown.
It is interesting that the cursor still finds the Center Line and Quick Selection also works on it, it is just that nothing is visible of it in the Floor Plan.
In the attached image, there are two Beams, the upper set in its Settings Dialog not to show the Center Line, the lower set to show it.
Beams are set in Model View Options to show Reference Line only.
Quick Selection senses the Beam and it can be selected.
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