[[duilioisola]]

Supongo que podrás solucionarlo utilizando Application.ProcessMesages.

Código Delphi [-]
procedure FormPrincipal.OnActivate...
begin
   {Aqui calcula cosas}
   Application.ProcessMesages;
   Calculo1;
   Application.ProcessMesages;
   Calculo2;
   Application.ProcessMesages;
   Calculo3;
   Application.ProcessMesages;
   Calculo4;
   Application.ProcessMesages;
end;