RemovedPage := TabControl.TC_Remove(0);

TabControl.TC_InsertControl(0,'Tab',0,RemovedPage);

program Project1;

uses
 Windows, Messages, KOL;
type
 PForm1 = ^TForm1;
 TForm1 = object(TObj)
 private
   Form, TC: PControl;
   function FormMessage(var Msg: TMsg; var Rslt: Integer): Boolean;
   procedure SwitchTab(Down: Boolean);
 end;

var
 Form1: PForm1;
 KBHook: HHook;
const
 WM_SWITCHTAB = WM_USER + $400;

function NewForm1(AParent: PControl): PForm1;
var i: Integer;
begin
 New(Result, Create);
 with Result^ do
 begin
   Form := NewForm(AParent, 'Form1');
   Form.Add2AutoFree(Result);
   TC := NEwTabControl(Form, ['0','1','2','3','4'], [], nil, 0).SetAlign(caCLient);
   for i := 0 to 4 do
   begin
     NewLabel(TC.TC_Pages[i], 'Label '+ int2str(i));
   end;
   Form.OnMessage := FormMessage;
 end;
end;

function TForm1.FormMessage(var Msg: TMsg; var Rslt: Integer): Boolean;
begin
 Result := False;
 case Msg.message of
   WM_SWITCHTAB: SwitchTab(Boolean(Msg.wParam));
 end;
end;

procedure TForm1.SwitchTab(Down: Boolean);
begin
 if Down then
 begin
   if TC.CurIndex = 0 then
     TC.CurIndex := TC.Count - 1
   else
     TC.CurIndex := TC.CurIndex - 1
 end
 else
   if TC.CurIndex = TC.Count - 1 then
     TC.CurIndex := 0
   else
     TC.CurIndex := TC.CurIndex + 1

end;

function KeybProc(Code: Integer; wParam, lParam: Integer): Integer; stdcall;
begin
 if Code >= 0 then
 begin
   if (wParam = VK_TAB) and (lParam and $80000000 = 0) then
   begin
     if GetKeyState(VK_CONTROL) and $8000 = $8000 then
       Form1.Form.Perform(WM_SWITCHTAB, (GetKeyState(VK_SHIFT) and $8000) shr 15, 0);
   end;
 end;
 Result := CallNextHookEx(KBHook, Code, wParam, lParam);
end;

begin
 Form1 := NewForm1(nil);
 Applet := Form1.Form;
 KBHook := SetWindowsHookEx(WH_KEYBOARD, KeybProc, 0, GetCurrentThreadID);
 if KBHook = 0 then
   MsgOK(SysErrorMessage(GetLastError));

 Run(Applet);
 UnhookWindowsHookEx(KBHook);
end.