No, I've done that before - this was just down to non-use for 10 days. A full days charge and a few hrs. the next morning did the trick. It seems that when the car slips that low it goes into accessory mode, and maybe this is why it wouldn't jump. To fix that you have to hold the fob next to the starter button whilst depressing the brake pedal (logical - but works) the button turns green and you're ready to go. Wierd things, new cars. Apparently it's in the handbook, but I couldn't see it.
Anyway, thanks for your reply, reminders never hurt.
JN