Workaround:
            
            this.radDropDownButton1.DropDownButtonElement.DropDownMenu.PopupElement.AutoSize = false;   
            this.radDropDownButton1.DropDownButtonElement.DropDownMenu.PopupElement.Size = new Size(300, 300);

RadSplitButton does not get a focus rectangle when focus by the Tab key. One should first click the action part and then the focus rectangle will appear..

The current workaround is:
public class MyRadSplitButton : RadSplitButton 
{ 
    protected override void OnEnter(EventArgs e) 
    { 
        base.OnEnter(e); 
  
        this.DropDownButtonElement.ActionButton.Focus(); 
    } 
}

Use the attached project to reproduce. 
- The first click should be disabled and the event should fire after the interval in the delay property. 

Workaround:
Me.RadRepeatButton1.Delay = 7000

when I use office2007blacktheme, the font of radbutton doesn't work.