If the cheese seems very moist, and easily grows unwanted molds, there was probably too much whey, and thus lactose, remaining in the curds from insufficient cooking (for a "hard" cheese). That might account for the rubbery spring you describe (though using too much rennet causes tough, rubbery curd as well). If there was too much lactose still in the curd, you may find the finished product tastes sour.
If you keep up with washing the rind with a light brine, you might find it naturally develops a tacky, then reddish-orange b.linens type ("stinky cheese") rind.