With "adjusting touch sensitivity in the setup" you mean in the FaderPort Firmware right? By default this is set to 7 - does it work in any setting?
I recommend installing MIDI-OX from
http://www.midiox.com/. Its a small tool that allows you to see the MIDI data being sent to/from your MIDI devices. Just make sure you select the FaderPort device in Options / MIDI devices. Make sure you don't do this with S1 running, as only one program at a time can open the same MIDI port to a device.
With that done, and your FaderPort in "waiting for Studio One" state, gently touch a fader but do not move it.
When you put your finger on top and then release, you should see the following MIDI being sent from the FaderPort to your PC:
If this is not the case I would contact Presonus support immediately, or just return the unit to the dealer where your purchased it from, and ask for a replacement.