I was disassembling and cleaning my Lido yesterday and found two odd things. First, I discovered these weird black spots on the outside part of the outer burrs where it comes in contact with the base. I tried to clean them with the provided brush and wet cotton cloth but with no success. Could that be dirt mixed with the oils from beans or water? Anyone else found these? I should have done some photos but it didn't occur to me at that time.

And second, when I assembled everything back together I found that there is a little play in the handle even if align the burrs so that they touch. That restricts any clockwise rotation as expected, but even though I tighten the screw that holds the handle pretty tightly I can move the handle a little in the opposite way. The shaft itself and the inner burr are not moving, only the handle (and the screw) is. I could tighten the screw even more but I think I would damage the screwdriver in the process. So.. is this normal and it's just that I haven't noticed until now?

Thanks!