The concept of Walter reminds me of the lead character "Gentle" in Clive Barker's huge fantasy novel "Imajica" (1991) because Gentle is an art forger (see Book reviews, March 28, 2006). The film has yet to be made.
Update: July 19, 2017
Jeffrey Tucker of the Foundation of Economic Education discusses the movie from the viewpoint of copyright, intellectual property, and creativity here. Electronic Frontier Foundation would agree with him.