How to extract exterior curve of curtain wall panels in plan

That is one area separator. Watch your list lacing. And levels closely. Perhaps try using @L1 for the view and sketch plane.

Thank you. If I get all the curves listed at the bottom of the Area Separator then how do I place them on my view?

When you see a number (Id) in the green box, dynamo has created an area seperator.
When you have an Area Plan view for the corresponding Level and you dont see them, check your Visibilty Graphics settings.
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