To be completely honest, using a VPN connection to play games is ill-advised. VPN connections, even under the most ideal circumstances, can incur notable increases in latency, severely crippling gaming performance. It can also interfere with geolocation caching processes, affecting match-making systems in many social MMOs. The above reasons, and even simply being detected using a VPN or proxy, can also result in game server bans.
That said, you can try using alternate server gateways and/or swapping ports and protocols within our application to help mitigate latency issues.
For UDP, try testing ports 9201, 1194, 8080
For TCP, try testing ports 80, 110, 443
Below are some other suggestions which may improve your connectivity:
Firstly, please power down your computer, router, and ISP's modem, wait approximately 60 seconds, then power each device back up in reverse order; please allow approximately 1 minute between powering up each device, to ensure they sync correctly.
Also, you can try updating your MTU setting, which may help your connectivity as well. Instructions on how to do so can be found in this article (please note these settings are not supported by us, and any changes are used at your own discretion and liability)
Beyond that, there isn't anything further that we can do, we apologize for any inconvenience this may cause. If you still have questions, please contact our support here.