Dimitrios Karras of Ares Armor noticed some discrepancies concerning the BATFE release of ATF Rul. 2015-1, specifically, their inconsistencies in ruling what exactly construes a receiver, a weapon, and the manufacture thereof.

Karras states the issue with a formal letter to B. Todd Jones, Director of the Bureau of Alcohol, Tobacco, Firearms, and Explosives:

http://aresarmor.com/store/NewsArticle/atf_rul2015-1

Click to access B.Todd%20Letter%20re%20Ruling.pdf

Given the problems with BATFE personnel understanding the technical and legal ramifications of their ruling, Karras provides a coloring book version describing the issue in crayon.

https://drive.google.com/file/d/0B99vEBRSpVxralZkNnlHOUFpeVk/view