Just got a new wacom for my mac, (my first one) and been practicing on it all weekend and having one big problem. Trying to lay in color on large area with brush. I pick my color for the fill box and leave stroke box empy. After a few seconds applyiny the fill, it will stop filling. Then when I click on what I've done, the stroke is same color as fill. When I correct the stroke by making it empty, it takes away a lot of the fill. Like the stroke was there to start with and I deleted it. Can you give me any advice?