Well, technically, it is possible but it would require that it be custom coded solution. I do offer custom development solution for Connections if you are interested. To contact me to define project scope and receive a quote, use the Contact link at the very bottom of the page.
As for updating with CSV, that too is possible. You would need the CSV Import extension. You would do you initial import with this extension. When you need to make changes, you would export the data from Connections as a CSV file, make your changes and then import it again. To do updates with a CSV file, you’ll have to use the CSV export from Connections, not from another source.
I hope I have thoroughly answered your questions.