Hi All,
Thought I would post the fix to this issue. This might not be the fix for all with the same problem but might help some one.

I got fed up with having to "play" the car on cold mornings and getting caught a junctions. So I took it the garage around the corner and told them the issue and about the connector. Left it with them and an hour later got a call to say it was ready for collection.
They connected the connector and connected the car to the PC, then reset the throttle limits and took it for a test drive.
It's been running like a dream since and drinking less fuel.

Not bad for £40.
Hope this helps someone else and thanks to all for the help and advice.
Canters.