We have two seasons here, winter and not winter. We get maybe three months of not winter. If it hits 80* people belly ache it's too hot.
Anyways, glad you found the knock sensors, they're an integral part of the GEMS suite. Like I pointed out to Ian, the TPS/Fuel Tank Pressure sensor could also be a possibility in the no start issue. Worth a look under the fuel pump cover, easier than the crank sensor. I have a couple more up my sleeve but we'll get there when we get there, you have to get it back together first. My day job is working with large complex machinery. A Rover in comparison is not very challenging.
The problem is that it is too difficult diagnosing things over the internet.
We are starting to grasp at straws.
He had stated previously that he had correct fuel pressure.
He stated that he had checked the injectors and they were putting out fuel.
He has tried starting it with adding fuel down the intake.
He has tried starting it with cutting out the fuel.
The above should indicate that it is not a fuel issue.
The compression test went nowhere near the fuel tank were the the issue your thread was related to.
A faulty TPS should not stop the motor from starting.
He has compression.
He has fuel.
By elimination, it is most likely something to do with spark.
He states that he has spark.
So this hopefully narrows it down to timing.
I have previously suggested finding TDC and then marking the pulley every 90 degrees to make sure that the spark on each of the 4 coils appear to be lining up correctly. I do not believe he has done this yet.
As the spark is controlled through the ECU, it could be at fault. He states that he has a spare ECU, but I have not heard whether he has fitted it yet.
I would therefore think that the next steps should be to change over the ECU and check the timing.
If that does not work, then we starting getting into things that should not stop the motor but maybe are for some reason.