Bruce, I used my 30w, so these settings might not help you. 
The voids were etched in cherry @ 5000 sp-30 pwr, and 450 sp-55 pwr to cut the paua. It leaves ash around the perimeter of the paua. The pieces are so small it was difficult to remove. I found rubbing the paua pieces on a plywood table top was enough to remove most of it, the rest I scratched off with my fingernail. 
I used medium CA to adhere the paua. I’ll run a couple on the 10w setting and let you know what the settings are. 

.................. John D....................