Pano2VR and Object2VR make occasional https requests to ggnome.com port 443 to check for updates, and it is also used during activation.
If you use Google Maps/OpenStreetMap/MapBox the map component connects to those services. The same goes for Google StreetView and the places API. Pano2VR then sends request to those Google APIs.
To preview an output project, the integrated web server opens a local port and opens this page in the default Web browser. Per default, this is a random port > 1024, and it is limited to “localhost”, but you can configure a dedicated port in the Pano2VR settings.