sample code showing how to update a paragraph properties using integration API

UpdateParagraphProperties.cs

var segmentPair = _editorController.ActiveDocument.ActiveSegmentPair;
var paragraphProperties = segmentPair.GetParagraphUnitProperties();

var newComment = _editorController.ActiveDocument.PropertiesFactory.CreateComment("Test Comment", "Test author",
    Severity.High);

if (paragraphProperties.Comments==null)
{
    paragraphProperties.Comments = _editorController.ActiveDocument.PropertiesFactory.CreateCommentProperties();
}

if (paragraphProperties.Comments.Comments.All(x => x.Text != newComment.Text))
{
    paragraphProperties.Comments.Add(newComment);
}

_editorController.ActiveDocument.UpdateParagraphUnitProperties(paragraphProperties);