This seems a thoughtful reflection on the verdict in the Harry Potter case - in which JK Rowling was seeking to prevent publication of a Harry Potter lexicography. The judge found in her favour. I'm mentioning it here since it is a topical (if complex) example of deciding how much you can and can't copy from one work in order to create a different kind of work - and it highlights the importance of synthesis! Thus it might be a useful example to use with learners.
Jones, P. (2008) The Harry Potter Decision, as text - Updated. 9 September. http://www.groklaw.net/article.php?story=20080909014304275
Photo by Sheila Webber: of a quidditch arena build in Second Life