Windows Firewall Stopping "easy Connect" From Working

First of all, I am no expert. I help out my inlaws in the USA with their PC remotely using MS Remote access ( msra.exe ). Everything works fine if they create an invitation file and send that to me along with the 12 digit number. However, I was looking at an easier way for them and me by doing it via the "easy connect" feature. My ipv6 is working fine and so is easy connect if I disable bitdefender firewall. Obviously I would like to keep firewall enabled during this process. With BD firewall enabled the ipv6 test site fails ( http://www.test-ipv6.com/ ) and easy connect does not work. With firewall disabled the ipv6 test passes all checks and easy connect works. What rules can I add manually to the firewall or indeed any changes anywhere else. I am running Win10 pro, BD Internet Security 2016. All programs are up to date. My inlaws have no easy connect problems as they are using Windows 10 firewall and Windows defender .Many thanks - Zippy ( Germany )