Another week has passed and answers to questions are getting a little bit technical...
However I picked up the car on Sat....the mechanic informed me that when the cylinder head had been skimmed the engineers failed to measure...consequently skimmed to much off...He said they should have checked the measurements ...this altered the clearance for the pistons which resulted in the timing going out and the valves blowing ...he said it was a nightmare ...he ordered a new gasket and full set of valves ....the engineers had to replace cylinder head ....and now all seems well with the engine ...The mechanic asked me to bring car back so he can flush remaining oil in the cooling system in two weeks at no extra charge...I DID POINT OUT TO HIM MY CONCERNS ABOUT THE OIL COOLER...but yet he has been consulting VW and suggests that my car has been correctly diagnosed.
One more thing that might be important to VW owners is that ,the mechanic strongly suspected that the head might have been skimmed in the past more than once.
Also the fact is as he says... the head can only be skimmed a max of three times.
Hope this is the end of the matter.
Many thanks to all who contributed replies ...you made me feel like i wasn't alone in this....