With my first algorithm, to move the circles of the eyes or the nose, I would redraw the previous shape in black and then I redraw it with color to its new position. This is a very simple way, but it make the screen a bit blinky...

From GFX Library, to move a "fillCircle()" in a direction, I used a hidden function called "drawCircleHelper()" to remove only a part of the border circle.