Hi Meet,
Thanks for your inquiry. We have inserted the contents of Object 2.docx into Object 1.docx using MS Word 2010 and have noticed the same paragraph formatting. We have attached the output document with this post for your kind reference.
Please move the cursor to the end of last paragraph’s text (of Lorem Ipsum.) and insert section break of type “New Page” using MS Word. You will see the same paragraph formatting.
To workaround this issue, please insert empty paragraph at the end of ‘Object 1.docx’ as shown below. Hope this helps you. Please let us know if you have any more queries.
Document mainDocument = new Document(MyDir + "Object 1.docx");
Document pieceDocument = new Document(MyDir + "Object 2.docx");
mainDocument.LastSection.Body.AppendParagraph("");
var importedSection = ImportSections3(pieceDocument, mainDocument);
mainDocument.Sections.Add(importedSection[0]);
mainDocument.Save(MyDir + "output.docx");