You would need at least the Pro version of CTA2 to do what you want.
The Pipeline version adds the ability to use the Flash/DrawPlus template to import everything at once rather than each body part piece by piece, angle by angle.
In the case of the Onion character, keep in mind that the same image was used for all angles for the head, body, legs and arms so that is was much simpler to construct than a normal character who usually has different images for each angle. Depending upon what your character is like you might be able to reduce the number of body part images by using the same image for multiple angles.
You would need some type of Photo Editor (Photoshop, PhotoPlus, etc.) to break up your image into the different body parts and to trim and touch up as needed.
If you haven't seen it yet, here is a link to the tut on creating the Onion character "Basic Character Body Creation"
See my CTA Tutorials on the YouTube channel CTAStepByStep
Check out EZColors for CTA. The easy way to change Render Styled (RS) colors.