Nevyn - Are you sure your Omniscope still has access to the Internet? What happens if you add a Web View (browser) to your IOK file? Can you see www.google.com?

It is possible you need to confirm/update the proxy server settings stored in your Omniscope installation here:

Settings > Advanced > Networking > HTTP/HTTPS Proxy settings

Nevyn - Thanks for sending us your sample file. The file opens with all map tiles displayed on several of our machines, so it is something to do with the online map tiling cache on your own machine. Try clearing this map tiling cache and cycling through several map options to see if this resolves the problem on your machine.