If your latest Rey theory has Kylo Ren knowing of her existence prior to meeting...you can throw that one out. Slashfilm reports that J.J. Abrams specifically stated that the two have never met, but that Ren has heard of her. Here's the specific verbiage...
“One of the new relationships that we were focusing on was between Kylo Ren and Rey. They’ve never met but he’s heard of this girl.”
While I don't know specifically what Abrams means in the statement, I would assume Ren's knowledge of Rey is limited to her escape from the New Order from Jakku. I don't think he's had people watching her and not acting on it if she is at all important to his plans.
I'm still of the mind that Rey's lineage is being made to be a bigger deal than it really is, and that the real climax of this saga is something we haven't even begun to think about yet. I'm also just over theories regarding where she came from in general as I think it's going to have only a small impact on the film overall. Really, everyone just wants justification for how Rey was so powerful in the Force and adept at using a lightsaber, which I'm sure is going to be answered by saying she is the child of a Jedi.