I think it would be best if the primary artwork on the Carrara box were both modeled and rendered in Carrara (and hopefully that was the case with c2 and c3). If non-Carrara objects are used (or any third-party plugins) then I think that should be clearly noted. A down-rev version of Amapi does ship with Carrara but it's not officially part of the base product. I guess it's a given that texture bitmaps will need to be created in an image editing program like Photoshop.