When shaping and rolling the dough into little balls, your fingers get sticky and the dough eventually builds up if you aren't constantly wiping your fingers on a paper towel or something. How to fix this problem: Pour a little rum or bourbon (you only need a tablespoon or two) into a small dish or glass and dip your fingers into it after every 2nd or 3rd rum ball. Your fingers will stay clean and every 2nd or 3rd rum ball has just a little "something extra". ;-) Works great!
GREAT TIP.... thanks