Workaround:
public Form1()
{
    InitializeComponent();
    this.radPageView1.RightToLeft = System.Windows.Forms.RightToLeft.Yes;
}

public class CustomPageView : RadPageView
{
    public override string ThemeClassName  
    { 
        get 
        { 
            return typeof(RadPageView).FullName;  
        }
    }

    protected override RadPageViewElement CreateUI()
    {
        switch (this.ViewMode)
        {
            case PageViewMode.Strip:
                return new CustomRadPageViewStripElement();
            
            default:
                return base.CreateUI();
        }
    }
}

public class CustomRadPageViewStripElement : RadPageViewStripElement 
{
    public CustomRadPageViewStripElement()
    {
    }

    protected override Type ThemeEffectiveType     
    { 
        get    
        { 
            return typeof(RadPageViewStripElement);     
        }
    }

    protected override bool IsNextKey(Keys key)
    {
        if (this.RightToLeft)
        {
            if (key == Keys.Left)
            {
                return true;
            }
            else
            {
                return false;
            }
        }

        return base.IsNextKey(key);
    }

    protected override bool IsPreviousKey(Keys key)
    {
        if (this.RightToLeft)
        {
            if (key == Keys.Right)
            {
                return true;
            }
            else
            {
                return false;
            }
        }
        return base.IsPreviousKey(key);
    }
}

To reproduce: 
1.Add a RadPageView with several pages. 
2.Set the ViewElement.AllowEdit property to true.
3.Use the following code:

public Form1()
{
    InitializeComponent();

    radPageView1.ViewElement.AllowEdit = true;
    radPageView1.ViewElement.EditorInitialized += ViewElement_EditorInitialized;
}

private void ViewElement_EditorInitialized(object sender, RadPageViewEditorEventArgs e)
{
    radPageView1.ViewElement.ActiveEditor.Validating -= ActiveEditor_Validating;
    radPageView1.ViewElement.ActiveEditor.Validating += ActiveEditor_Validating;

    radPageView1.ViewElement.ActiveEditor.Validated -= ActiveEditor_Validated;   
    radPageView1.ViewElement.ActiveEditor.Validated += ActiveEditor_Validated;    

    radPageView1.ViewElement.ActiveEditor.ValidationError -= ActiveEditor_ValidationError;
    radPageView1.ViewElement.ActiveEditor.ValidationError += ActiveEditor_ValidationError;
}


private void ActiveEditor_Validating(object sender, CancelEventArgs e)
{
    RadPageViewElement.PageViewItemTextEditor editor =
        sender as RadPageViewElement.PageViewItemTextEditor;
    
    if (editor != null && radPageView1.ViewElement.ActiveEditor.Value == string.Empty)
    {
        e.Cancel = true;
    }
}

private void ActiveEditor_ValidationError(object sender, ValidationErrorEventArgs e)
{
    RadMessageBox.Show("Page label can't be empty!", "Error", MessageBoxButtons.OK, RadMessageIcon.Error);
}

private void ActiveEditor_Validated(object sender, EventArgs e)
{
    RadMessageBox.Show("Page label has been successfully updated!", "Information", MessageBoxButtons.OK, RadMessageIcon.Info);
}


If you change a tab title and do not press Enter, but click outside the pageview, the respective events for validation are not fired.

Workaround:
private void ViewElement_EditorInitialized(object sender, RadPageViewEditorEventArgs e)
{
    RadPageViewElement.PageViewItemTextEditor textEditor = e.ActiveEditor as RadPageViewElement.PageViewItemTextEditor;
    RadPageViewElement.PageViewItemTextEditorElement element = textEditor.EditorElement as RadPageViewElement.PageViewItemTextEditorElement;
   element.PropertyChanged += element_PropertyChanged;
}

private void element_PropertyChanged(object sender, PropertyChangedEventArgs e)
{
    RadPageViewElement.PageViewItemTextEditorElement element = sender as RadPageViewElement.PageViewItemTextEditorElement;
    if (e.PropertyName == "ContainsFocus"&& !element.ContainsFocus)
    {
        radPageView1.ViewElement.ActiveEditor.Validate();
    }
}

To reproduce:

Create a RadPageView and add these items:

RadPageView pageView = new RadPageView
{
    Parent = this,
    Dock = DockStyle.Fill,
    ViewMode = PageViewMode.Outlook
};

pageView.Pages.Add(new RadPageViewPage("Machines"));
pageView.Pages.Add(new RadPageViewPage("Users"));
pageView.Pages.Add(new RadPageViewPage("Software"));
pageView.Pages.Add(new RadPageViewPage("Queries"));
pageView.Pages.Add(new RadPageViewPage("Reports"));
pageView.Pages.Add(new RadPageViewPage("License Manager Servers"));

You will see that the Users and Reports items will be auto ellipsed.

Workaround:

Change the font of the item. Changing the style should be enough:

foreach (RadPageViewItem item in (pageView.ViewElement as RadPageViewOutlookElement).Items)
{
    item.AutoEllipsis = false;
}

To reproduce:
- Add RadPageView with a two pages to a blank form, each page should contain a RadGridView.
- Populate the gids with some data.
- Start a gotomeeting and show your screen.
- Launch the application or start debugging.
- Add a column to the first tab page (not sure if the location or placement matters)
- Click the tab header for the second tab page to try to navigate to it
-  Nothing will happen.

Workaround:
- Change focus to another application.
-  The test app will now update.

To reproduce:
- Implement the example from this page http://www.telerik.com/help/winforms/pageview-how-to-editing-page-tabs.html.
- Set the page text to empty string and click on another page.


Workaround:
subscribe to the editor's element RadPropertyChanging event:
void element_RadPropertyChanging(object sender, RadPropertyChangingEventArgs args)
{
    if (args.Property == RadElement.ContainsFocusProperty)
    {
        if (!(bool)args.NewValue)
        {
            args.Cancel = true;
        }
    }
}

RadPageView does not show the individual tabs close buttons when they are enabled in the form constructor.

In order to reprocude:
- Add RadPageView
- Add RadPageVIewPage (or two)
- Add couple controls to the bottom right corner or the page (aligned with the and of the page)
- Set those controls Anchoring property to Bottom, Right

Start and the controls are in a different position then the they were located.