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Click the Add Label button:
A Label dialogue will open:
Give the label a name and click the Create button:
A label will appear on the map with its given name.
You can move the label around the map using left-click+drag with your mouse. You can also update its available properties whilst it has been chosen for editing.
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Click the Ruler button on the Configuration Options:
A red line will appear on the map with a distance specified:
You can then move the points around the map to suit where you would like to display a distance between one point to the other by clicking on the white spot and dragging it into position:
The distance will be automatically updated for you.
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