Art Brush tool

Hello, and thank you in advance - I could really use some help, please. 

Working in latest version of Animate and trying to use the Art Brush tool with Cintiq 2200.   It was working fine for a few minutes yesterday - nice tapered strokes (my first time using it), and then....it was gone, the problem persisting with both mouse and tablet pen.   At the same time,  I the stroke changed to this hollow look, which seems connected...

   I am trying to regain the tapered line with ink art brush.  When I draw, I get a flat wimpy line -- the same line regardless of point size.  100 points, or one, it looks the same.   I did a bug fix ("repair") in Creative Cloud (wouldn't let me uninstall it), I uninstalled and reinstalled Animate.  Restarted several times.  Granted, I am just learning, but I have done my due dilegence and cannot figure out what I have done to this file to make it misbehave so badly!  Thank you for taking a look..