Warning lights. Help!

[brightondave]

Hi I have a C4GP 1.6hdi VTR+ 2009
I've owned and loved for the last 5 years. 149000 miles serviced fairly regularly and it flies through mot's yearly.
About a week after the mot the eml came on and I found when it beeped and triggered the email the engine would cut out at about 60 mph and i'd have to coast to the side of the road, restart the car and it would be fine again, I have a little old tester and the usual suspects came up :
Low fuel pressure
Major fuel leak
High pressure fuel regulation and P1351
So I did a bit of research and after a period of time came up with a possibly blocked dpf or egr valve blocked.
So without involving a main agent and paying £150 for a diagnosis I initially tried a bottle of Wynns Dpf Cleaner and went for a 7 mile drive down the main drag, strangely every thing was ok which it normally is up to 66mph until ping the em's kicked in big time quoting :
Abs / Esp fault
Handbrake fault and Service light came on.
So pulled into a lay by, checked the Internet, which told me to with the engine off, turn the ignition on and off 3 times, which I did and pulled away from the layby, then all the eml lights disappeared and I carried on home without any loss of power or limp mode or anything.
So basically what happens now if I put up with it, if I dont push it past about 65mph its ok, the original fault which used to cut the engine never happens now for some unknown reason.
So without booking it in somewhere and it costing me the earth and I'm relieved of £300 - £700 only for it to return a week later?
Any advice on this is appreciated, from anybody to whom it may have happened before to?
And anything that I may try going forwards?
Thanks for reading this.