If they downlded fine with no problems connecting or speed, then the problem is somewhere in your set up or else, poor sources or poor ultrapeers you are connected to. Sometimes disconnecting & reconnecting can give you fresh ultrapeers & a better session.

Did you try deleting your LW preferences yet? It might be worth the try.

When you said you set UPnP, which modem or router brand & model is it you set it with?