ts not a tx/rx wiring error because the sensor is correctly working with the sfg demo, the problem is with arduino, and thats why i got to watch at the libraries.
You forgot the link to that SFG Demo program but I guess it's a software for a Windows PC. So how can you tell that the wiring for the Arduino is correct if you never had a working software on the Arduino?
I've already suspected that but the datasheet are exactly the same
So you have a datasheet for that part? Why didn't you post it here?
Are you sure you gave us the correct type? The manual I found for that type string says the connector has 5 pins. On the posted picture I can see 6 wires.