Another Pan. Nv-gs35 transfer query.

Hi to all, this is my first post.
I know there is another transfer post similiar to this, but mine is a bit different.
Bought a new Panasonic nv-gs35 camera in Thailand last Nov, and also a friend did the same. We are both having the same problem, different cameras (same model) and different computers. Using Usb, i was able to transfer from camera to Pc first time, but the film was very jerky. However I now cannot get anything to record on to the computer, and nor can my mate with his.

I have not got a fire thingy cable, should I get one?

The programme comes up on the computer but there is just no recognition that the camera is playing (though the camera screen shows it is fine).
Any ideas.
Chris.