Please refer to the attached screenshot. It is not possible to localize the marked label.

Workaround:

 Sub New()
     InitializeComponent() 
     Me.RadRichTextEditor1.RichTextBoxElement.InsertHyperlinkDialog = New CustomInsertHyperlinkDialog()
 End Sub

 Public Class CustomInsertHyperlinkDialog
     Inherits InsertHyperlinkDialog
     Protected Overrides Sub OnLoad(e As EventArgs)
         MyBase.OnLoad(e)
         Me.Controls("radLabel4").Text = "My address"
     End Sub
 End Class

Workaround: use a custom RichTextEditorRibbonBar

Public Class CustomRichTextEditorRibbonBar
Inherits RichTextEditorRibbonBar

    Dim headerText As String
    Protected Overrides Function GetInsertTableItems() As RadItemCollection
        Dim collection As RadItemCollection = MyBase.GetInsertTableItems()
        Dim headerItem As RadMenuInsertTableItem = TryCast(collection(0), RadMenuInsertTableItem)
        headerText = "My Header Text"
        Dim fi As FieldInfo = GetType(RadMenuInsertTableItem).GetField("header", BindingFlags.NonPublic Or BindingFlags.Instance)
        Dim header As LightVisualElement = fi.GetValue(headerItem)
        header.Text = headerText
        AddHandler header.TextChanged, AddressOf header_TextChanged
        Return collection
    End Function

    Private Sub header_TextChanged(sender As Object, e As EventArgs)
        Dim lve As LightVisualElement = TryCast(sender, LightVisualElement)
        If lve.Text = "Insert Table" Then
            lve.Text = headerText
        End If
    End Sub
End Class

Currently all tables are stuck to the let and there cannot be a text before them.

To reproduce:
- Click the AA Styles button to open the Styles dialog.
- Scroll down and select the CodeBlock item
- The style does not change


 

Workaround: 
public class CustomRadRichTextEditor : RadRichTextEditor
{
    /// <summary>
    /// Gets or sets the width of the caret.
    /// </summary>
    [Browsable(false)]
    [Category(RadDesignCategory.AppearanceCategory)]
    public new float CaretWidth
    {
        get
        {
            float caretWidth = base.CaretWidth;
            if (float.IsNaN(caretWidth))
            {
                return 2;
            }

            return caretWidth;
        }
        set 
        { 
            base.CaretWidth = value; 
        }
    }
}

how to reproduce: check the attached video

The bullets can have their own alignment. Implement import and export of this setting.

In MS Word, this alignment can be set through the Numbering dropdown -> Define New Number Format

How to reproduce: check the attached video

To reproduce:
 - Add a table where the width is set to 100%
 - Import the table and the export it:
private void radButton_Click(object sender, RoutedEventArgs e)
{
    var provider = new HtmlFormatProvider();
    string text = File.ReadAllText(@"..\..\default.html");
    rtb1.Document = provider.Import(text);
}

private void radButton1_Click(object sender, RoutedEventArgs e)
{
    var provider = new HtmlFormatProvider();
    provider.ExportSettings.StylesExportMode = StylesExportMode.Inline;
    string content = provider.Export(rtb1.Document);
    File.WriteAllText(@"D:\test1.html", content);
}

Workaround:
 Leave the export mode intact.

Workaround: Set the next style property for all types except the Paragraph to an empty string
foreach (var style in this.radRichTextBox.Document.StyleRepository)
{
    if (style.Type!=Telerik.Windows.Documents.Model.Styles.StyleType.Paragraph && !string.IsNullOrEmpty(style.NextStyleName))
    {
        style.NextStyleName = string.Empty;
    }
}

1. Create a document containing a style with NextStyleName:

           StyleDefinition myStyle = new StyleDefinition();
            myStyle.Type = StyleType.Table;
            myStyle.DisplayName = "My Style";
            myStyle.Name = "myStyle";
            myStyle.NextStyleName = RadDocumentDefaultStyles.HyperlinkStyleName;

            this.radRichTextBox.Document.StyleRepository.Add(myStyle);

2. Add several paragraphs and select some of them (ensure there is one using our custom style).

3. Create a DocumentFragment using the selection's CopySelectedDocumentElements

4. Convert the fragment to RadDocument and try to export it

Observed: When exporting to DOCX and XAML, the style is missing. Exporting to RTF causes KeyNotFoundException.

Expected: The style should be preserved in the exported document

Workaround: After creating the document from the fragment, ensure all needed styles are copied and available.

To reproduce:
- Open the demo application.
- Go to the Table Styles example.
- Open the TableBorders dialog from the context menu and hit reset all.

Workaround: 
private void RadRichTextEditor1_CommandExecuting(object sender, CommandExecutingEventArgs e)
{
    if (!(e.Command is PasteCommand))
    {
        return;
    }

    DocumentFragment res = ClipboardEx.GetDocumentFromClipboard("RadDocumentGUID");
    if (res == null)
    {
        foreach (ClipboardHandler settings in ClipboardEx.ClipboardHandlers)
        {
            res = ClipboardEx.GetDocumentFromClipboard(settings.ClipboardDataFormat, settings.ClipboardStringFilter);
        }
    }

    if (res == null)
    {
        e.Cancel = true;
        System.Drawing.Image bitmapSource = Clipboard.GetImage();
        if (bitmapSource == null)
        {
            return;
        }

        Telerik.WinForms.Documents.Layout.Padding sectionmargin = this.radRichTextEditor1.Document.CaretPosition.GetCurrentSectionBox().AssociatedSection.ActualPageMargin;

        double originalPixelWidth = bitmapSource.Width;
        double originalPixelHeight = bitmapSource.Height;

        if (originalPixelWidth == 0 || originalPixelHeight == 0)
        {
            originalPixelWidth = 10;
            originalPixelHeight = 10;
        }

        double width = originalPixelWidth;
        double height = originalPixelHeight;
        
        if (this.radRichTextEditor1.Document.LayoutMode == DocumentLayoutMode.Paged)
        {
            Section currentSection = this.radRichTextEditor1.Document.CaretPosition.GetCurrentSectionBox().AssociatedSection;
            Telerik.WinForms.Documents.Model.SizeF pageSize = (Telerik.WinForms.Documents.Model.SizeF)currentSection.GetType().GetProperty("ActualPageSize", System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.NonPublic).GetValue(currentSection);

            double maxWidth = pageSize.Width - (sectionmargin.Left + sectionmargin.Right);
            double maxHeight = pageSize.Height - (sectionmargin.Top + sectionmargin.Bottom);
            width = Math.Min(maxWidth, width);
            height = Math.Min(maxHeight, height);
        }
        
        double ratio = originalPixelWidth / originalPixelHeight;
        width = Math.Min(width, height * ratio);
        height = width / ratio;
        
        Telerik.WinControls.RichTextEditor.UI.Size size = new Telerik.WinControls.RichTextEditor.UI.Size(width, height);
        ImageInline imageInline = new ImageInline(new WriteableBitmap(bitmapSource));
        imageInline.Size = size;
        
        this.radRichTextEditor1.RichTextBoxElement.ActiveDocumentEditor.InsertInline(imageInline);
    }
}

To reproduce: 
- Load a right to left document with Hebrew characters.
- Export it to PDF
- The characters' position is not correct.

Workaround: 
private void RadRichTextEditor1_CommandExecuting(object sender, Telerik.WinForms.Documents.RichTextBoxCommands.CommandExecutingEventArgs e)
{
    if (e.Command is SaveCommand)
    {
        DocumentPosition initial = this.radRichTextEditor1.Document.CaretPosition;
        DocumentPosition start = new DocumentPosition(initial);
        DocumentPosition end = new DocumentPosition(initial);

        var spans = this.radRichTextEditor1.Document.EnumerateChildrenOfType<Span>();
        foreach (var span in spans)
        {
            if (span.FontStyle != FontStyle.Regular)
            {
                continue;
            }

            start.MoveToInline(span);
            end.MoveToEndOfDocumentElement(span);

            this.radRichTextEditor1.Document.Selection.AddSelectionStart(start);
            this.radRichTextEditor1.Document.Selection.AddSelectionEnd(end);

            this.radRichTextEditor1.RichTextBoxElement.Commands.ChangeFontFamilyCommand.Execute("Calibri");
        }

        this.radRichTextEditor1.Document.CaretPosition.MoveToPosition(initial);
    }
}

Please refer to the attached screenshots. A sample .docx file is attached. Just load it in RadRichTextEditor. 

Use attached to reproduce.