Yea TE port testing fails when I try to host, and ping fails sometimes when I want to join
I did encounter some wierd thing thought. One program was telling me that my port is open, put online port checkers where saying that it is closed...so I was completley confused on what to do...
However, I did fix it last night, someone suggested before to use Skype port, which in my case was 8277. I tried it few days ago and it did not work. But also seems after I made factory reset on router, that some issues on router got fixed, as after that I even manage to open other ports (altought they again gave me udp port error), this one port 8277 got working without an error.
So I don't get an error anymore
You can add that somewhere in documenation as possible solution for people that experience it