Greetings--well reporting back as promised:
Could not see any big issues with pins or ECM, but then that that only means nothing very obvious to me!
I cleaned MAP, it was not very dirty in itself but I also pulled out fair bit of gunge from inside the mount/pipe (not the sensor hole I stress)
I did a small drive to pick kids from school after (5 miles round trip up a big hill) and it got to temp and on arrival home it was still functioning and EGRs were showing 25%-35% on live data so i got excited and thought wehey sorted, it was the MAP!
but then after sitting on idle for 10 mins then giving it a push above 3k revs the fault came back, so starting to suspect it kicks in at high revs/load.
I am a bit concerned that very quickly this will go outside my comfort zone as well as taking too much of any good peoples time here explaining faults to me. So spoke to a very reliable mechanic I know who has, over the years, saved me thousands on multiple cars so going to leave the car with him for however long it takes to find the issue and sort it.- he hadnt done the recent work i stress for a host of reaosns around location of the initial fault, and so had to bite the bullet to go back to him as it was a bit like confessing to adultery having been to another garage!!
think thats really only logical thing I can do as it does sound and feel like it wont be an easy diagnosis or fix to find here, i had rather been hoping someone would say--ah yes that fault is xxx and this is the fix
learning it is never that simple with a Disco lol
I will report back once it is sorted to advise what was found in hope it may help another in my position
thanks