Td5 struggling when cold

Hi all, now am getting all my bits and bobs sorted on my 02 plate discovery. The one big bug I need to fix,
Start the disco she fires fine ( is cold temps winter will cut straight out but will run on second time) engine seems to idle low them about 5-10 seconds revs pick up to normal idle, but if you hold the throttle down half / 3 quarters the engine revs but like a lack of power and what seams to be white smoke out the back, and a misfire or 2, but the strange bit if you bring the clutch up 2 drive off the lack of power is unreal and about 20secs boom she's off but when pulling away from junctions she's abit gutless

Know problem with my car
1. The high pressure line from the in tank pump to the filter has had a repair at some point with rubber hose.
2. MAF IS un plugged the plug needs repairing,

MODS To the disco that might help.
1. EGR removed blanked
2. Regal sport decat system
3. All new 5 copper and rubber injector seals
4. New injector harness
5. No oil in red plug

Any ideas will be good

injector seals would be my 1st port of call

First move would be to check the glow plugs and fix the MAF thing cos it can take between 10 - 15 seconds for the ECM to "realise" that the MAF is not there and go to default cos on Eu3 engines the injection is managed based mainly on MAF/rpm readings and the default is based on MAP.... did you clean the MAP sensor after the EGRR was removed?...if not do that asap

Has had new copper and rubber seals on the injectors along with plunger reset

Yeah map sensor was clean. I have noticed if the car has been running and you nick it off and turn the key straight back on with in 1-2 seconds the fuel pump in tank is priming again is this right ?