控件构造函数需要的是AOwner TComponent，而不是Parent

constructor TCustomLabel.Create(AOwner: TComponent);
begin
  inherited Create(AOwner);
  ControlStyle := ControlStyle + [csReplicatable];
  Width := 65;
  Height := 17;
  FAutoSize := True;
  FShowAccelChar := True;
  { The "default" value for the Transparent property depends on
    if you have Themes available and enabled or not. If you have
    ever explicitly set it, that will override the default value. }
  if ThemeServices.ThemesEnabled then
    ControlStyle := ControlStyle - [csOpaque]
  else
    ControlStyle := ControlStyle + [csOpaque];
end;