Well after my repair guy looking at it for a week, it actually fired up only to stop in the same original manner. He is inclined to think that it's a combo of corroded wiring and dodgy alarm, (Meta 357T) so I asked him to remove it, but he says it's not as easy as that due to were it may have been channeled into. I now have to be patient and wait until he has time to finish the job. (What with everyone wanting their bike ready for summer and George Whites closing)
Ah well, at least it's less expensive than replacing an ecu!!