New cap ordered, checked wiring and it all looks ok to me.
Have changed coil with the one next to it, will see what happens.

Ok I did look it up on the bmw parts catalogue but it looks like it comes as one

It's a difficult one, at the end of the day you're going to be paying someone a lot of money to get your car back on the road.

Whilst you're waiting you could ring a couple of specialist places and ask what they actually do when a vehicle comes in with problems such as yours.
At least that way you'll have choices when BMW do get back to you.
I'd still be pushing for the full cost though.

BMW are not repairing the box just replacing with a reconditioned unit, ( is that correct ).
If so then you can get prices from gearbox specialists for exactly the same work, you will get a warranty for at least 12months.

I'd be looking elsewhere to be honest, have you got any prices from gearbox specialists.
If you think BMW missed the problem before then stand your ground and refuse to pay any amount.

That's good to hear.
I'll experiment a bit regarding the lumpy acceleration when in cruise control.

Sounds like a plan to me, I'll do this and see if it makes a difference.
Fuel cap is on properly, although I did notice that the rubber o-ring/seal is cracked, could that cause this?

When I use cruise control and increase the speed via the + button on the steering wheel the car takes off like a rocket, is this right, I would have thought it would just slowly increase until I let go. Then when I've finished using cruise and simply press the loud pedal the car doesn't like it at a...

I've noticed lately that when I start from cold the engine idles a bit lumpy after starting up fine, maybe 30 secs later. Then, and I thought it was my imagination, it seems to "hunt" a little whilst being driven, I can see the rev counter moving slightly, but again, this seems to go once ...

How do you set the steering wheel to adj to your position when inserting the key and them retract when removing the key

DPF- Diesel particulate filter.
As far as terra clean goes, I would worry more about having so little oil in the car before anything else.

Lots more info needed on history of car, but basically you need to get it to a decent garage that has the correct equipment to tell you what's wrong, it's an expensive hobby if you start to guess and replace random parts.

Bluetooth?