What exactly do you mean by "insert an unlinked body in a part"? Do you mean you have an existing NX part file and you would like to take it, ot at least some object(s) in it and move them to an existing part? If so, have you tried using 'Copy & Paste'? Also, you could use...
File -> Import -> Part...
...to merge the contents of one NX part into the current Work part.
You can also go the other way round as well, that is with the part file open that contains the objects of interest, you could use...
File -> Export -> Part...
...to take selected objects and insert them into an existing NX part file.
You can also use WAVE and then simply break the link(s) so as to remove any connection with the original part file.
As for your question about extracting a surfaces, I assume that you mean to extract a surface from the face of a solid model. If that's the case, then you can use...
Insert -> Associative Copy -> Extract Geometry...
...to accomplish that.
Anyway, I hope that helps.
John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Digital Factory
Cypress, CA
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