AtomX on Suzuki F6A - Trigger issues on cranking

I've got a Suzuki Cappuccino with the stock F6A and AtomX. It has a 12-1 trigger wheel on the crankshaft, reluctor sensor mounted with a <1mm air gap to the sensor. Trigger 2 is the standard cam position sensor with 3 teeth, 1 per TDC, so I am using cam pulse window for sync, the window being 40 degrees before tooth 6. It used to start second or third try, which I put down to bad cold start tuning. In theory, nothing at all has changed since then. I now have a no start fault where I

For a VR sensor the length of the tooth should be about the same as the diameter of the pole inside the sensor. Often this is about 4mm. If the pole is not externally visible (they often poke out the end) then you can get a feel for the diameter of the pole by dragging a paperclip across the end of the sensor and the magnetic bit is the pole. But the length of the teeth I dont think would stop it from running - it will more likely just stretch out the wave form and give you poor accuracy as p