dectar se shift esta pressionada

tenta o seguinte:

No evento OnKeyPress

if key = chr(16) then begin
//processamento
end;

ValueMeaning

ssShiftThe Shift key is held down.
ssAltThe Alt key is held down.
ssCtrlThe Ctrl key is held down.
ssLeftThe left mouse button is held down.
ssRightThe right mouse button is held down.
ssMiddleThe middle mouse button is held down.
ssDoubleThe mouse was double-clicked.

procedure TForm1.FormKeyDown(Sender: TObject; var Key: Word;
Shift: TShiftState);
begin
if shift =ssShift then
// xxxx
end;


[]´s

no evento onkeydown
if tbKeyIsDown(VK_SHIFT) then