Dave
I am unable to pinpoint your exact problem from the diagnosis, perhaps some one with more diagnostic experience than I (Mike Smith, Teknome on here ? ) will be able to do so , but what I do have is the Rover 14CUX fuel injection manual which I can send to you.
It is a large file (6.2MB) even as a pdf, so better sent as an email attachment rather post here. If you pm me with your email address I send it today.