On a side note, only install add-in files from developers you trust as doing so allows third-party code to run on your documents.
Once Word is up and running, you should see a new tab at the top of the Word menu that says ADD-INS--similar to what you see above.
Click that tab and you'll see menu item for word usage. Select it and a pop-up appears with a bunch of options that are all straightforward tweaks you can make to the frequency report.
Once you're ready to go, click OK and your word frequency report will appear as a new document--unless you changed that setting.
That's about all there is to setting up the add-in. Enjoy your word frequency counting!
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