It always amazes me when correspondents who post in these pages hoping for advice that may lead to the remedy for a problem they can't sort, refer to interfering with the 'engineering mode' of the infotainment unit.it does not make good reading.
'137699' expressed a similar sentiment when he responded to the OP in the thread to which you allude in this manner:
You've taken the unit out of the car?
You don't need to take it out to update it....
I'm afraid I don't have much sympathy here. You've been meddling with stuff that you really shouldn't...