I have run this motor now for more than 10 litres - and still working out a few bugs - which I list here for comments and for others to try when troubleshooting.

1. Problems on the tune - for me this was dirt in the carb pre filter - solution run a fuel line filter and keep it clean.
2. Needles should be around 1.5 turns - more than 2 turns, or very sensitive - clean the carb.
3. Support the plug lead - and don't let it move / vibrate - the outer braided sheath will break where it is soldered to the plug cap, if stressed - recommend tape ?
I got servo jitter, when turning the ignition switch on, and no starting with this problem.

And todays BIG one -

4. If impossible to start - and does not appear to be flooded, when you check the plug. And there is no sign of fuel line problem,
Have a check of the reed valves.

Comments here please - I was surprised to see a problem with the reeds.
I found the carbon reeds were open about 2-3mm and look warped,
My solution - for now - was to take the reeds off and put back on - up the other way -
This reduced the gap to maybe 0.5mm - 1 mm and closed easy.

Another check of the reeds - without disassembly - seems to be - take the crackcase pressure line off the carb - and turn the motor over - if you can hear it sucking and blowing hard - the the reeds are sealing when the pistion is going up and down ?

My starting process involves
Choke on, ignition off, throttle low - Bounce prop from compression to compression 5 or so times.
Choke on, ignition on, low throttle - With a couple flips - Starts and stops
Choke off, ignition on, low throttle - Then 3 - 4 flips - Running and flying

Any suggestions to these problems - and comments are welcome, especially if I am doing it wrong !!!

Cheers
Dom