Notation Imput

Updated from MS 4.5 to 4.51 hoping to control when MuseScore Inputs notes via Midi into a score. Before upgrading I could either from my computer or piano keyboard control when MS would input data into the score. With MS 4.5 and 4.51 I've lost control of that essential function. As it stands now, I cannot touch my midi keyboard without the data being entered on the score.