Trivia: Mark Hamill received $1 million for his role as Luke Skywalker, despite the fact that he does not appear until the very end of the film and has no dialogue at all.
Trivia: Although Harrison Ford is first billed, he does not appear until 38 minutes into the film.
Trivia: Lor San Tekka (Max von Sydow's character at the start) is never referred to by name.
Answer: The First Order already has the piece that R2-D2 was carrying as well. That is the first piece, the large piece of the map missing a small section. The second piece is carried by BB-8 and only by BB-8, the missing piece in the map. All the first order needs is that second piece, and so does the Resistance. However the Resistance needs R2-D2 to activate again so he can show them the first piece, so they can put the second piece in it.
lionhead