hapans:

I remember the initial conversations about having things ‘skinned.’ Peeling away layers to evolve into other people. And the person Kylo’s pretending to be on the outside is not who he is. He’s a vulnerable kid who doesn’t know where to put his energy. But when he puts his mask on, suddenly, he’s playing a role. J.J. had that idea initially, and I think Rian took it to the next level. – Adam Driver

hapans:

Ren believed [the droid] was no longer valuable to us. That the girl was all we needed. As a result, the droid has most likely been returned to the hands of the enemy. They may have the map already.

So the idea here is that Kylo Ren’s gotten inside of Rey’s head, sees that she has seen the map, and is now letting go of the droid as his goal, and focusing just on her. And clearly you think—well, he must be able to just extract the information he wants now. But because he’s taken her, you get a sense that there might be something else going on here. – J.J. Abrams