new set up with battery smoke

I have two other pack, but they are the same sheap ones. I found the connector that burned out on the battery pack. I disessemled everything...I really think all the wires are in place. I have attached pics. Please let me know if anything is wrong. The only thing I can think of is poor conections. If I put the plug into the receiver for the the UBEC or speed controller the wrong way (they went into the right port), would that cause it? If so, how can you tell which is the right way?

I just orderd a set of IB 3800 and 5mm plugs. I will assemble the batteries and shorten the wires on the controller and revamp the connections.