Downloaded tours are completely indepedent of CloudPano's servers. The only exception is if your downloaded tour has Lead Capture turned on.

When a user completes the Lead Capture form on your tour, the email is sent through CloudPano's server. You do not have to be connected to CloudPano for this form to work, and you don't have to be Pro Plus. We made the design decision as this allows the most people to use lead capture on their downloaded tours without requiring technical know-how to create their own email server.

All downloaded tour assets, images, code do not connect to CloudPano. If you do not use lead capture you will never connect to CloudPano on a downloaded tour.

For more information, check out this article: Do I need to remain subscribed to CloudPano to use downloaded tours? Do downloaded tours expire?