The update is this. P200E engine in and sorted, HT coil was the culprit, would idle fine, perform badly when given throttle. I have a replacement stator on the way, it's dragging its bum a bit though, been over two weeks since I arranged it, in the meantime I have a borrowed stator that's just fine...
Yesterday I rode to Geelong for a club breakfast, started out having only done about 120-130kms on the new engine prior, but it was the perfect weather, cold and the road is also perfect, mostly flat, some hills varying in slope and of course some sweeping bends. I've opted for a ride it like I normally do type of run in, sans taking it WOT, so far it hasn't missed a beat, other than a few idle adjustments and clutch tweak, I haven't had to do anything, all I need now is for the rain to give me a break to ride more.
As for the other engine, it's pulled down, cleaned and is going into a real Veloce case, no rush on it though, like the 75cc rebuild, it can wait, I'll do it bit by bit.
What a journey from A to B it's been.