I'm so sorry, but I prefer to keep these kinds of questions on the Tumblr blog so they're more easily accessible to everyone (commenting here would eventually get buried and lost) ^^;
The link you were talking about in the FAQ currently has all the information available to guess Ren's name, so you're welcome to go through it if you need more clues!! It also includes a few posts where I mention that his name is not Warren or Soren.
If you still have more guesses, please submit them to the Tumblr blog!! I appreciate your interest in trying to figure out Ren's real name ^^