Hi all and Bert and Dave

Just to follow through:
* Tank choice: you must not use a tank which will not stand gas. The Glo ones (semi transparent, like the Kavans) are soft and will get even softer with time as gas is present. I had a perfectly going engine which went gradually worse with time and found the tank had got much too soft. The pressure from the exhaust pipe was upset by this softness.
Now I use the Dubro's and they are good. You can use the chinese transparent ones too, if you have room enough. They stay stiff. So use them both for the main tank and also the crap trap, for the same reasons.
Then, miracle, engine transitions are much better and everything is more predictable. Good.
* engine curve: I had some hard time with this one because the Thr position did not correspond to the carb opening position. So I got rid of it, Explanation is perhaps that the curve gives it a kind of expo shape, where the 3 last points (50% 75% 100%) had to deal with about half of the total opening. No good because not precise unless you have a valve curve with a lot more points than the 9 we advise. So, slow down the servo and get rid of the Thr curve.

Have a good time ! really worth it indeed !