I came across this forum today - but solved this from a slightly different approach. - This places the compass rose on the the map in its location - rather than a layout element
In the ArcGIS Maritime Server Install files there is a directory
C:\Program Files\ArcGIS\MaritimeServer\Server12.0\customchartbuilder\CompassRose
A Filegeodatabase and a lyrx file
Make a copy of this directory and you can paste this to your working project
Add the lyrx file to the map
If necessary point the source data to the compass rose feature in the file geodatabase
Now you can add points in the location(s) you desire - save your edits
Now you can use the tool Calculate Magnetic Components
and map the fields to the Value of Annual Change in magnetic variation and the Value of magnetic variation.
(Or if you know these values - you can populate these in the attribute table manually - you will still then need to save your edits after this)
Either method will change the rose as shown here. (image(15).png)
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