Unable to order shapes sweep2 as turning corner 2 rails become one and a pivot point

I have been ultra careful , I can now see where the problem lies.
Couldnt see this error in help or google.
sweep2 rails with the 8 curved profiles,
profiles made from circle three points
rails from a rectangle project to a cylinder surface
inner rail from edge of a box.
all are I think healthy.
its the corners that fail it, nothing to do with unable to order shapes and the error message.
I presume corners must be sweep1rail and pick the two profiles.
I need to keep the arc as profile on all sweeps.

Its a weld line, wish there was a weld making command. I am recreating visually something, else I would say weld here !

file attached.
unable to order shape for sweep2.3dm (32.7 KB)


Yep, you cannot have shape curves that touch - do it in sections.