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Open the System Menu, select the User to open the User Details screen.
Click on the Background Display tab and click Edit:
Select the desired Background Map Type. In the example below Google Map has been chosen:
You can then select the Google Map Tile Type: Displaying a Map
Then click Save.
Close the User Details screen and there will be a new Map Opacity option within the PPI Navigation Control:
Moving the slider to the right will make the background image more visible:
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