Offline updating through the firewall

I have searched the forum and not found any suitable (up-to-date) responses.

I have a PC connected to 4 laptops on a wireless LAN. The laptops are all managed remotely using TightVNC as they are located outdoors. Each is used to record data from a webcam on a 24x7 basis.

My objective is to allow full access on the LAN but no access to or from the internet for the laptops - only through the PC. However, I would like for the Comodo Antivirus database to be updated regularly.

In order to maximize security I have created a network zone which is included under the allowed tab, and then excluded all other addresses in the blocked tab (this has to be typed in as the range of IP4 addresses of the network and the exclude box then ticked - I cannot create a network zone called ‘internet’ because the only place to create it is in the ‘allowed’ tab, and obviously I don’t want it there!). While this stops all internet access for the laptops, it also means that the antivirus database cannot be updated.

As I understand it, these network zone rules over-ride the global and application settings.

Since I allow internet access on the PC, is it possible to update the antivirus databases from my PC, which is automatically updated?

Otherwise every few days I have to manually remove the blocked addresses, carry out a manual update and then retype the IP addresses back to re-block internet access.

Or is there another alternative way of manipulating global settings that I am not aware of?