Re: Post remap advice
could be maf or map sensor.
did Oggie tap in to measure the boost pressure of the turbo? (may not be able to if the car doesn't have a boost gauge fitted)
Maf will sometimes cause slow spool up, making the car really laggy, tends to cause under fuelling, you could try disconecting it...
Map sensor will mess with the amount of boost, you need more boost to get more power - it would be good to know what boost its running.
EGR - just a pain in the... as a test you could just cap it off with a bit of coke can to see if it makes a difference.
Split boost pipes - you would normally hear the turbo whistling more, possibly signs of oil from where the leak is, depending on the size of the hole, a drop in boost pressure - again, handy to have a boost gauge.