I've just put two of the company Focus Tdi's into the garage (2008 reg), one of them has gone in because the sales rep said it kept on cutting out (has about 60,000 on the clock).
they changed the fuel filter and had no luck. They then called me about an hour later and informed me that they have no record of the dpf regeneration additive going in the car on the third service, infact the last two services had been missed (our reps are responsible for their own servicing).
They put the additive in and serviced the car. Luckily this solved the issue and it has now stopped cutting out.
Now the next Focus (2009 with about 52,000).... This one started cutting out and hasn't missed a service, but the dpf is unusally blocked to the point it is totally knackered. I was initially quoted £1400 inc fitting and they reduced the quote to £800 after a bit of shouting. Ford actually recommend that the dpf is changed at 75,000 miles!!
Both cars are now parked up and will be sold as seen, as there is no point wasting any more money on them.
Not sure on your other issues, but the cutting out might have something to do with the dpf.
Andy