Bitmap brush tools not working properly

I just got ToonBoom Storyboard Pro 4 and am trying to use the standard bitmap pencil tool on a bitmap layer. But for some reason, if I’m zoomed out less than 100%, the image on my stage is disjointed and blocky, and will jump about. Whatever I draw seems to look fine down in the panel/timeline area, but not on the stage. Notice the attached image.

Is there a bug or issue with the software? Has this been remedied yet? Or am I doing something wrong here?