I have used the Roverguage software to extract a ROM image. Then I have modified the contents and blown a new ROM. I was only changing some of the diagnostic code as I wanted to enable the MIL light (also need to amend wiring). I have steered clear of amending fueling as I spent a few years getting an Omex fuel map correct and have the badge, and scars. I do have an early version of a Blackbox MSV which will talk to the 14CUX, the immobiliser, and also the GEMs, only downside was the price. Best place for info is Piston Heads - Gassing Station - TVR group.
