Been a while, but this has now been resolved so thought I'd let you know what caused it...
The eventually wouldn't start and the battery also went dead as it had sat for a while as I tried to decide the best course of action .
So I had it transported over to the guys at Horsham Developments.
After some deep thinking and investigation on their part they discovered that the flywheel had been fitted incorrectly when I had it changed along with the clutch over 1.5 years ago The crank position sensor had also given up the ghost. (along with a cam sensor needing swapping).
The zed has had a full service now also and it runs like new, so nice to be able to enjoy the car once again.
I cannot thank Jez and Craig enough at Horsham Developments, those guys are great and listened to my ramblings and made sense of it to get the car back in shape. Can't recommend them enough!!
Big thanks guys, I now know where my zed should go for any work