It takes me a few frustrating minutes to figure out that drawing in Anime Studio is very different from drawing in Flash. I'm used to using my tablet to draw, and in Flash you can draw much as you would on paper. Anime Studio does provide a freehand drawing tool but it's not as easy to handle and feels more constricting. There's also no eraser, so adjusting a hand-drawn line involves selecting points on that line and moving them or deleting them individually.
In fact, Anime Studio behaves more like a 3D modelling program - it makes more sense to construct your lines and shapes rather than draw them, and once I've adjusted my expectations it gets easier. It seems the idea is to import a picture you've created on paper or in another program, and then reconstruct it in vector form using the drawing tools. So I imported an image of my Graham character and set about tracing over it, trying to produce exact copies of the original hand-drawn lines because hey, I'm obsessive like that. It's painstaking work and far from quick, but the tools give you a satisfying amount of control once you learn what they all do. I abandoned the tablet for the mouse, and after half an hour I'd constructed a passable copy of Graham in the workspace and could turn off the tracing image.
NOTE: The first attempt was problematic. I drew an outline of the head shape using the Freehand tool and then used the paint bucket to fill in the grey tone. For some reason this resulted in slightly jagged edges on the vertical strokes (even with antialiasing switches on and even when the image was exported), and there seemed to be no way to fix the problem. On the second attempt I used a basic circle shape and then added extra points to it, shaping it into the bent lozenge that is Graham's head. No jagged edges this time, so I assume that the way to work in Anime Studio is to build as much as you can from basic squares, circles and triangles.
After tracing Graham I made a version of another character I've been messing with for a while, and then I built a robot from scratch using only the basic shape tools.
Once you get used to the keyboard shortcuts to switch between tools you can manipulate shapes quite easily. It's mildly annoying that you can't select multiple points using any tool other than the actual Select tool, because I frequently wanted to adjust several points at once and had to keep flipping between tools to do it; but maybe I'm just a whiny prick for whom nothing is ever quite good enough. On the whole, the drawing tools are very slick, and for people who've grown up with computers rather than paper probably more or less perfect.