Charlie asked, what can be done incorrectly when fitting an ECU, well plenty, bad earth, parts of harness running along parallel to plug leads, no shield on the crank or cam sensor, bad connections, etc.
I agree with ECU monitor, in the way he said the crank sensor signal should be checked. I don't want to start an arguement with anyone, and repect to each poster, but this is a very interesting thread.
John