Manual Node Placement in Version 5
Start by importing your jpeg file. In the Image menu change the image to monochrome, and then rather than use the Accuscan tool, use the Graphic Edit Tools on the left side of the CAD/CAM window, but more importantly, use Node Edit.
By placing nodes around the object, I was able to better follow the contour of the image than the Accuscan would give me. After I did the outside area, I focused on all the inside portions to gain as much detail as possible. Notice the Red and Blue nodes placed around the collies head.
Once I was finished placing the nodes, I selected the Original, and pulled it off to the right. Select eh new image, make path, break path, and then Connect path to an allowable error of .15 inches. This will help to close any gaps in the internal features of the collie.
When I use the Show Fill tool to see the view of the solid parts, it looks almost exact to the original.
This method, though longer in labor time, may give you the results you are looking for. Accuscan can be great for working with simple shapes, but I really think this method gives you more freedom to create the images you want to produce.