Whats all the fuss about being connectable & why should I care?
If you are not connectable it means that you are firewalled or NATed and cannot accept incoming connections. Therefore you cannot share properly. This means that other peers in the swarm will be unable to connect to you, only you to them. Even worse, if two peers are both in this state they will not be able to connect at all. This makes life harder for uploaders & obviously has a detrimental effect on the overall speed. The way to solve the problem involves opening the ports used for incoming connections (the same range you defined in your client) on the firewall and/or configuring your NAT server to use a basic form of NAT for that range instead of NAT (the actual process differs widely between different router models. Check your router documentation and/or support forum. You will also find lots of information on the subject at PortForward).
