Dica: Simular Click do Mouse

No Delphi, para simular um Click do Mouse deve ser usado a API Mouse_event.

Exemplo:

uses
  Windows, ...
.
.
procedure TForm1.Button1Click(Sender: TObject);
var
  p1, p2: TPoint;
begin
  GetCursorPos(p2);
  p1 := Form1.ClientToScreen(Point(Form1.Edit1.Left,Form1.Edit1.Top));
  SetCursorPos(p1.X+5, p1.Y+5);
  Mouse_event(MOUSEEVENTF_LEFTDOWN, 0, 0, 0, 0);
  Mouse_event(MOUSEEVENTF_LEFTUP,   0, 0, 0, 0);
  SetCursorPos(p2.X, p2.Y);
end;