Hi Glen, the vehicle hasn't been back (at least not for the original fault) so I can only assume it's fixed, as I was doing this for another garage I never spoke to the Espace owner, but I imagine he would let us know as it was often dangerous to drive when pulling out of junctions etc.
We changed the Maf as the peak reading was low, this gave the vehicle lots more mid-range power, also fuel filter housing and pipes seemed to improve things too but we were still getting air bubbles in the feed pipe. We removed the tank and examined the swirl pot, pressure and vac tested it and also all pipes under the vehicle including the fuel cooler, found the feed pipe from the tank wouldn't hold vac so changed the pipes.
Did an extended road test with no problems, it had never run so well, thought we'd fixed it, opened the bonnet for a final check and the bubbles were still there! If I recall the owner needed it back for a few days so we let him take it, shortly after he returned to pay his bill but I dont know how that conversation went, can only assume he was happy with it. It's been back for other work since and the customer isn't local so he must still be happy with it...
But I never had any fault codes, read with a Solus, Dec and a clip. The only problem in live data was the actual fuel pressure when compared with the desired pressure, that amount increased as the loss of power got worse. It sounds a little different to your fault, i remember when the misfire started, it wouldnt accelerate, even flooring the pedal had no effect apart from making the autobox kick down a gear or two.
Hope this helps.