anchor.diff:      begin
         NumSection      := NumSection - 1;
         NumPageSection  := T_Section(Sections[Pred(NumSection)]).NbPages;
  -      Bv_Visu.Visible := False;
         with T_Section(Sections[Pred(NumSection)]), F_Visu do
         begin
           Bv_Visu.Height := Paper.H;
           Bv_Visu.Width  := Paper.W;
  -        Bv_Visu.Top    := 50 + (F_Visu.Height - 50 - Paper.H) div 2;
  -        Bv_Visu.Left   := (F_Visu.Width - Paper.W) div 2;
  +        RepositionPage;
         end;
  -      Bv_Visu.Visible := True;
       end
       else
       begin
  
positive.code:     NumSection      := 1;
      NumPageSection  := 1;
      E_NumPage.Text  := IntToStr(NumPage);
      Bv_Visu.Visible := False;
      with T_Section(Sections[Pred(NumSection)]), F_Visu do
      begin
        Bv_Visu.Height := Paper.H;
        Bv_Visu.Width  := Paper.W;
        Bv_Visu.Top    := 50 + (F_Visu.Height - 50 - Paper.H) div 2;
        Bv_Visu.Left   := (F_Visu.Width - Paper.W) div 2;
      end;
      Bv_Visu.Visible := True;
      ChangeButtons;
      E_NumSect.Text     := IntToStr(NumSection);
      L_NumPageSect.Text := IntToStr(NumPageSection);
  
negative.code:     NumPage         := T_Section(Sections[Pred(NumSection)]).FirstPage;
      NumPageSection  := 1;
      E_NumPage.Text  := IntToStr(NumPage);
      with T_Section(Sections[Pred(NumSection)]), F_Visu do
      begin
        Bv_Visu.Height := Paper.H;
        Bv_Visu.Width  := Paper.W;
        RepositionPage;
      end;
      ChangeButtons;
      E_NumSect.Text     := IntToStr(NumSection);
      L_NumPageSect.Text := IntToStr(NumPageSection);
  