Importing a document with block-level content controls from XAML causes them to become corrupt. If you scroll to a position in which the said control is only partially visible a NullReferenceException is thrown.
A possible workaround would be to initially save the document as a DOCX (just exporting it to DOCX will not fix the issue as the information is already corrupt).
Another way to reproduce this issue:
1. Create a new document and insert a Rich Text Content Control.
2. Save the document as a XAML file.
3. Reopen the XAML file.
4. Move the caret inside the Content Control.
5. Try to insert a new line by hitting Enter - no new line is added as the content control is marked as Inline Level after the import in step 3.
Case 2:
Create a document with TOC where the content control of the TOC contains some other inlines.
In MS Word,create a new docx file, insert a table, select the whole table, insert a bookmark.
Open the docx file with RadRichTextBox, the bookmark is missing.
This is because the bookmarkStart is in the first tc, while the bookmarkEnd is after the last tr, TableImporter failed to import the bookmarkEnd.
Here is my fix.