Miami & Rams with Unfair Advantage??

With only one hour and fifty three minutes until the draft (but who's counting), the first pick has already been made. Early this week Miami signed Jake Long to a contract as an offensive tackle. But the NFL told the Rams that they cannot do the same, even though now it's their turn.

I may be missing an angle to this, but:

1. Why let Miami make their first pick days before the draft (giving the Rams a slight head start that no one else will get)
   
2. Why only let the 1st pick go and then hold up the rest?
   

I really don't get it. Will someone enlighten me?