well i don't know about anim8or but blender is open source and they say you are free to change the code and sell it it if you want.
from the blender site:
"Can I distribute the official blender.org releases under my own branding and name?
Yes, you are free to name Blender whatever you like, and repackage and distribute it under your own branding, provided you still deliver or publish it under the GPL conditions to your clients.
You can NOT change Blender's copyright notices, nor make claims you wrote or created that program.
Without explicit permission, you then can also NOT change existing claims or credits that have been published for Blender, such as feature or specification listings on blender.org, galleries or movies, release notes, screenshots, press articles, reviews, and so on.
If you wish to rename and/or rebrand Blender, you will have to create and use your own credits and achievements as well.
"Can I sell my own version of Blender?
Yes you can, but only if you provide this new version of Blender and the sources to your clients under the same GPL license. The client then benefits from all rights the GPL offers; free to use it, or even distribute it when they wish.
This method provides an essential business model for contracting and support business with Blender. You can freely sell fixed or changed code in Blender, for as long you deliver this as GPL to clients. You don't have the obligation to publish it for everyone."
