To Cidolphus:
I remember to open ports, you have to type 192.168.1.1 in your address bar to access your router, and then go to Applications & Gaming, then click the sub-tab that says 'Port Range Forwarding' and then do this:
Start ~ End Port should have 55296 to 55551 (that's what I have at least), select UDP from the Protocol selection, and then make sure 100 is in the space in the IP address part. Then have 'enabled' checked on that line and save your changes. This is what mine looks like and the patcher works fine for me.