Hi Leemz,

Findports.com says that you also need to open ports 34297 for both TCP & UDP.

Yes, you will also need to open these ports in your Windows Firewall AND in your router. I don't know what version of windows you're using, but this guide will give you the general idea for how to open ports in Windows firewall:

http://www.rfactor-league.com/rFactor/ConfigPorts.html

I also respectfully recommend that you disable these ports once you're done playing.