How about just buying more bits to experiment with? 
I have the extra accessories but ignore my BitZero and just use the tissue paper gauge as an exercise of simplicity.
After trying all kinds of hold downs, my favorite is wide painter’s tape on an MDF waste board. I hot glue around the perimeter of the wood or aluminum that I need to mill for a secure grip.
Just paint rubbing alcohol onto the hot glue to release the hot glue/painter’s tape and the finished product will pop off.
Easy peasy . . . this is not Tool And Die Shop