I've had to put a Astra down as the model for this post, but the vehicle I need help with is a Zafira!

I've a friend who's recently bought a 2003 Zafira 2.0 DTI with a known poor starting problem, it would generally start when cold but not when warm. To cut a long story short and after trying various things he was told to buy a new diesel pump. His has the ECU on top with 2 large connector blocks,1 at either end so a 2nd hand one from an 03 Astra was bought and fitted but it won't start at all now. He then bought the OPCOM interface and software in the hope of reprogramming the new ecu, which he was told he had to do, he has security codes, vin numbers for both pumps but when he runs the software and enters the security code for the new pump there is a message about 'security wait time' which he's been told is around 4.5hrs. After 4.5hrs he goes back to the laptop and its frozen! Has anyone been able to reprogramme an ecu using OPCOM? I read somewhere that an ecu has to be 'unpaired' from the donor car prior to refitting on another. Can anyone help, are we trying to solve a problem that isn't solvable with OPCOM? He's getting desperate so any advice, pointers or step by step guides (!) would be greatly appreciated!! Thanks.

hi i know its a silver ecu but does it looked sealed on the bk of the ecu you,ll see like sealent on the bk of it

if you can see sealent on the bk of it it can be opened to look for dry joints on the solider take it to a car electians if you dont want to do it yourself on the original pump ecu some ecus cant be opened for repair that should get the car going