How to use Curve (2D) with broken segments of circles?

[[Ri...]]

I have 2 cylinders, at the entry of each cylinder is a full circle scan.
The lower circle has to be broken into two segments.
When I recall these into a 2D Curve, they don't calculate properly. I don't know how to describe what it does, but it doesn't work.
The reason I have to break up the last scan is due to the depth is greater than the Stylus I have available, so I rotate B 5 degrees (285°-150°) at B-5° and (105°-150°) at B5°.
I'm using "Curve Distance" to calculate wall thickness.

It works great with closed circle scans. 🙄

Diameter 3.55
Length 4.65

Any help is appreciated.

Curve my other eye.JPGCurve my eye.JPG