When exporting a document in a Silverlight project using the XamlFormatProvider an exception is thrown.

Italic bullet sign of bulleted paragraph (with last italic characters) is exported like an equal sign with a line through it.

Workaround: Make all italic bullets non-italic. The following code achieves that:

RadDocument document = this.radRichTextBox.Document;

foreach (var paragraph in document.EnumerateChildrenOfType<Paragraph>())
{
    if (paragraph.ListId != Paragraph.ListIdProperty.DefaultValue)
    {
        DocumentList documentList = document.ListManager.GetDocumentListById(paragraph.ListId);
        int levelIndex = paragraph.ListLevel != Paragraph.ListLevelProperty.DefaultValue ? paragraph.ListLevel : 0;

        if (documentList.ActualStyle.Levels[levelIndex].NumberingFormat == ListNumberingFormat.Bullet)
        {
            documentList.ActualStyle.Levels[levelIndex].SpanProperties.FontStyle = FontStyles.Normal;
        }
    }
}

this.radRichTextBox.UpdateEditorLayout();

Occurs for properties of paragraph like alignment or ListId as well.

Many common words with apostrophes fail spell checking (isn't, shouldn't) while others pass (don't, can't). 

Word traversal (GetCurrentWord, etc.) breaks words apart on apostrophes.

When styling the whole paragraph and exporting to HTML format the list item doesn't receive its styling. On importing the output document we can't recover the full styling of the list item.

Even if a cell is aligned to center or right, the td element in the HTML has attribute align="left". The paragraph within has the proper alignment, but this is confusing.

MS Word omits the align attribute of the cell and sets alignment on the paragraphs directly.

All attributes for table cell are exported to HTML regardless of whther they are added to HtmlExportSettings.PropertiesToIgnore or not.

A document created from RadRichTextBox containing a transparent image is successfully shown in Adobe. However, when saved from Adobe, leads to corrupt PDF and the image is missing.

At this point the Ctrl + Insert shortcut doesn't work, while the Shift + Insert is pasting the text in the editor, but the pasted text is not visible until you start to type. 

The calculation of the left and hanging indent is incorrect for paragraph in list when the left and hanging indents are with the same value.

The exception can be observed when printing document containing images with unsupported formats, or images with empty source (RawData = "").

The exception is with the following call stack:

   at Telerik.Windows.Documents.UI.HeaderFooterContainer.UpdateUI(SectionLayoutBox sectionBox, Boolean delayed)
   at Telerik.Windows.Documents.UI.HeaderFooterContainer.UpdateUI(SectionLayoutBox sectionBox)
   at Telerik.Windows.Documents.UI.DocumentPrintPresenter.MeasureOverride(Size availableSize)
   at System.Windows.FrameworkElement.MeasureOverride(IntPtr nativeTarget, Single inWidth, Single inHeight, Single& outWidth, Single& outHeight)


Workarounds:

If you click on print preview and print the document from the preview it is working;
     2. Use the following code

        this.radRichTextBox .PrintStarted += Rtb_PrintStarted;

        private void Rtb_PrintStarted(object sender, EventArgs e)
        {
            RadRichTextBox rtb = (RadRichTextBox)sender;
            foreach (var floatingImage in rtb.Document.EnumerateChildrenOfType<FloatingImageBlock>()
                                                      .Where(fi => !this.IsSupportedImageFormat(fi.ImageInline.Extension))
                                                      .ToList())
            {
                floatingImage.Parent.Children.Remove(floatingImage);
            }

            foreach (var inlineImage in rtb.Document.EnumerateChildrenOfType<ImageInline>()
                                                    .Where(i => !this.IsSupportedImageFormat(i.Extension))
                                                    .ToList())
            {
                inlineImage.Parent.Children.Remove(inlineImage);
            }
        }

        private bool IsSupportedImageFormat(string format)
        {
            return (format == "jpg") ||
                   (format == "jpeg") ||
                   (format == "png") ||
                   (format == "bmp");
        }   

I am using a HtmlFormatProvider control to display html memo. But there is an issue that this control will display nothing if the wrong color number in html. Ex, if you set html like below, the control display empty. it should ignore the error and display rest of message. Thanks
previewControl.htmlDataProvider.Html = "<table >\r\n<tbody>\r\n<tr>\r\n<td align=\"left\" valign=\"middle\" height=\"30px\" bgcolor=\"#cccccc\" style=\"height:30px;font-size:12px;padding-left:3px;bgcolor=#cccccc;font-weight:bold;color:#00001;border-bottom:1px solid #000001;\">\r\nItem number</td>\r\n</tr>\r\n</tbody>\r\n</table>"