You can append individual curves that make up a continuous curve.
For example, when you generate curves from boundaries or discontinuities you may end up with a set of curves, as shown below. This is because of the Polyline Break Angle setting.

You can append these curves to create a single curve. This curve can then be easily picked as a surface boundary.

To append curves:
on the main toolbar to display the Curve Editing side toolbar.
on the Curve Editing side toolbar.CopyCAD appends the curves, creating a single curve that is shown in a single colour.
| Note: If you select curves that intersect, or that do not meet at the ends, CopyCAD displays this error message "Couldn't append curves. Please ensure that the curves you have picked form a continuous curve". |