She turns over first time but idle and turbo gauges fluctate and it sometimes dies immediately, or If I give it some gas it's OK. BUT always as soon as press the brake pedal and move into Drive or Reverse she stalls.
This happens 3 or 4 times then I can move off, but it's rough for the fist mile.
Car has only 30k miles on it. It's a UK B200FT

Anyone have any suggestions?

 

I can't solve your problem (though I really wish I could), but this is EXACTLY the same issue I'm having with my 1986 Volvo 760 Turbo. Exactly. It's really upsetting!