So here we go - got the car back after 10 days............ here's a synopsis of what they did :
1. Faulty camshaft positioning sensor
2. Timing out
3. Faulty Cylinder head
4. Faulty non return valve (a known GTI Mk 6 problem apparantly)
5.Inlet camshaft damaged
6. Camshaft bearing damaged
7. Fitted new cyinder head
8. Fitted new camshaft
9. Fitted new head gasket
10. 1 x wheel bearing faulty so that had to be replaced too
11. Faulty ignition coils - replaced
12. New spark pugs
All done under warranty.
They told me the root cause of all this was the faulty camsgaft positioning sensor and non return valve. Apparantly, 60-70k miles is the normal time for these to go. The fault was know about on the VW maintenance databse

To end this with good news I would say the car is performing better than before with massive increase in acceeration and performance. Fuel consumption down though

I hope none of you get this problem too.