Hi LSM,
the change-over took 20minutes, mainly because the head of one screw was rotten. Otherwise it would have been faster. Built my own flywheel-holder out of the rest of a book case (yes, it does look as sorry as it sounds, pic upon request

), but it did the job.
I took R6-coils cause I had them lying around here. I bought them some months ago after reading
The Flute's coils topic.
Standard coil is still available but these are better, can post a pic of the R6-ones if you like.
Both parts were at fault: the resistance values of the exciter coil of the stator were out of range (values are in the manual). Plus the clip on the ignition coil (which holds the HT leads) was broken, the HT leads were being held in place with a tie wrap

. Furthermore one of the needles (thorn?) in the coil, where you put the HT leads on, was nearly missing......
Now it starts again a first kick, but (new) without the need of the choke and it idles instantly.
cheers,
Charles
PS weather here in North Rhine-Westfalia isn't any better as it is in Kent...