The fix will be available in the next official release Q1 2015. 

PdfFormatProvider creates an invalid PDF document. 

Workaround:

RadDocument radDocument = null;
XamlFormatProvider xamlformatProvider = new XamlFormatProvider();
using (FileStream inputStream = new FileStream("input.xaml", FileMode.Open))
{
    Console.WriteLine("reading input file");
    radDocument = xamlformatProvider.Import(inputStream);
}

var provider = new Telerik.Windows.Documents.FormatProviders.OpenXml.Docx.DocxFormatProvider();
var bytes = provider.Export(radDocument);

var provider2 = new Telerik.Windows.Documents.Flow.FormatProviders.Docx.DocxFormatProvider();
var flowDoc = provider2.Import(bytes);

var provider3 = new Telerik.Windows.Documents.Flow.FormatProviders.Pdf.PdfFormatProvider();

using (Stream output = File.OpenWrite(@"output.pdf"))
{
    Console.WriteLine("writing output file");
    provider3.Export(flowDoc, output);
}

Console.WriteLine("done...");
Console.ReadKey();

Custom Paragraph or Linked styles are not applied when used in Headers and Footers.

Documents containing <pre> tag and line breaks (CR LF) cause unexpected visual behavior (loss of content) and invalid layout. Sporadically, document positions seem to also get invalid which leads to exceptions.

To reproduce: 

InvalidOperationException: 'ColumnSpan must be at least 1.' is thrown when importing HTML document with table column containing colspan="0".

The colspan="0" has special meaning according to the HTML specification http://www.w3.org/TR/html401/struct/tables.html:
-------------------
colspan = number [CN]

This attribute specifies the number of columns spanned by the current cell. The default value of this attribute is one ("1"). The value zero ("0") means that the cell spans all columns from the current column to the last column of the column group (COLGROUP) in which the cell is defined.
-------------------
Workaround: Preprocess the HTML, and delete all occurrences of colspan="0".

To reproduce:

• Create two lists one after another
• Select the second by using the keyboard 
• Press delete and then Ctrl+z (undo)

This works fine when the list is selected with the mouse. 

Hello,

   We found a problem when using the radrichtextbox control. When radrichtextbox is enabled to cancel input, error will be reported using the sougou Chinese input method. This problem will not occur in the English input method. Please help solve it. Thank you very much.

When the copied document fragment is replaced during paste within a single RadDocument:

ClipboardEx.SetDocument(new DocumentFragment(doc));

Ordered list are not pasted correctly.

Workaround:

Bypass paste and use the InsertFragment API

this.radRichTextBox.InsertFragment(new DocumentFragment(doc));
e.Cancel = true;