There are three places where you can download data as a CSV file in Local Brand Manager.

The first place is the Dashboard of your GBP location. If you scroll down below the general breakdown for the GBP on the Dashboard page, you will see the statistics for that GMB. At the top right there will be a button to Export to CSV. This will give you all your data based upon the date range you set at the top left of the insight report.

The second is the Keywords section available on the left side panel. When you click the checkbox on any of the keywords, a menu will appear. Using it, you can export your keywords to a CSV file. The CSV and CSV V2 have different table structures, but contain the same data. The Ranks History CSV will guide you through your keyword ranking changes over time.

The third CSV export is accessed in the Live and Scheduled GeoGrid Search. If you go to Live GeoGrids and click on the history tab, you'll see the list of all the GeoGrid searches that you've run. Click on the three dots and a dropdown menu will appear. The "Download CSV" link will give you the file.

For scheduled GeoGrids, go to the Configs tab, pick a config, select a keyword you want a CSV file for and click CSV.