Adding breakpoints (markers) to particular lines in code should be possible.

Should be doable via UI or in code. Collection of all breakpoints should be accessible in code too.

Depending on the current layout of the document, invoking SetPosition() for a specific location might result in positioning the caret on the line prior to the expected one.

Steps to reproduce:

• Create a document using the following code:

radRichTextBox.Insert("one: ");
radRichTextBox.Insert(Environment.NewLine);
radRichTextBox.Insert("two: ");
radRichTextBox.Insert(Environment.NewLine);
radRichTextBox.Insert("tree: ");
radRichTextBox.Insert(Environment.NewLine);
radRichTextBox.Insert("four: ");
radRichTextBox.Insert(Environment.NewLine);
radRichTextBox.Insert("five: ");
radRichTextBox.Insert(Environment.NewLine);
radRichTextBox.Insert("seks: ");
radRichTextBox.Insert(Environment.NewLine);
radRichTextBox.Insert("seven: ");
radRichTextBox.Insert(Environment.NewLine);
radRichTextBox.Insert("eitgh: ");
radRichTextBox.Insert(Environment.NewLine);
radRichTextBox.Insert("nine: ");
radRichTextBox.Insert(Environment.NewLine);
radRichTextBox.Insert("ten: ");

• Place the caret at the end of the "nine: " line
• Invoke SetPosition():

radRichTextBox.Document.CaretPosition.SetPosition(radRichTextBox.Document.CaretPosition.Location);
radRichTextBox.Focus();

Observed: The caret is positioned after "eitgh:"

Expected: The caret shouldn't change its position

Add support for shapes, and especially for shapes with textual content. 
In OOXML, shapes are represented by the wps:wsp element, and shapes with textual content by <wps:txbx>, <w:txbxContent>.
Such shape can be added to a Word document using the Insert -> Text -> Text Box -> Draw Text Box, or through a shape's context menu -> Add Text.

Note: Do not confuse with Text/Rich Text content controls (https://feedback.telerik.com/Project/143/Feedback/Details/113730 ).