Gas Problems, Help!!!

We were getting a new gas oven in today and the gas man came and said that the previous job (not done by us) was not only put in by a cowboy, but was illegal as it used plastic pipes and not copper pipes to transport gas to the extension where the kitchen is and the oven is obviously located. He said that it put our lives at risk and he turned off the gas and it cannot be reconnected till its fixed (big job) on Thurs!!!! Just in case he was chancing his arm I rang a friend who is a builder and he looked at it and said the same. Therefore no heat as the gas into the house is turned off!

I believe that all of these plastic pipes (they look like water plumbing pipes) will have to be replaced with copper pipes and then certified by the Gas board.

What I am essentially wondering after this shock is, have I:
(a) Any comeback on my engineer who did a survey of the house prior to purchase?
(b) A certificate of compliance was issued by an architect when the previous owners built this extension is there any comeback there?
(c) Do I just except that the previous owners were numtys who sold us a dangerous dud of a system and just foot the cost myself and move on.

Thanks for your opinions.

Can't answer all the questions, but as far as I am concerned, the surveyors take no responsibility for anything (surprise, surprise). If there is a certificate of that extension being in accordance with the regulations, you might have a case there.

Anyway, you are lucky you found out about that. It is very dangerous!!