I have a 2013 Volvo. I joined this site and downloaded speed cams. They uploaded to the Volvo, but the cams do not appear on the map. I tested it with the large file for Maryland, and no thing showed up. I then uploaded just the 30MPH cam file and scrolled over on the map to a known 30 MPH camera. It's not there, but it shows up in the file when I browse it on the POI page.
I choose garmin GPX (and have tried the one with proximity alerts). They load, but don't show up.
Save your files as a Garmin GPX file using the Extra POI converter. You can also select the GPXx option.
Copy all downloaded/created GPX files to any USB stick and import them to your Volvo GPS.