When you hit "Upload CSV to S+" and get the missing cities.csv message as shown in the following dialog, it can only be one of three issues.

- Make sure the CSV configuration is set in the latest league file location - see https://wiki.statsplus.net/web-tools/csv-configuration
- Make sure the CSV gets dumped from OOTP. When the config file is in place, dump the CSV in OOTP: Game->Game Settings->Database tab, upper right drop-down, pick "Export Data to CSV Files" as shown here:

or you can also use the Automator and make sure the "Export data to CSV files" box is checked like:

- Lastly, make sure the league folder setting in the S+ app points to your latest saved_games folder, you can find the full path on your PC following https://wiki.statsplus.net/en/faq/folder-location-html
You can use the steps in #3 after doing 1 and 2 and navigate into the import_export/csv folder and confirm there are 70+ CSV files there, then double-check it's the same folder using the folder icon next to the path entry box in the S+ app.