I think the Rams will take a player that has OG potential at some point. Maybe even 2. The Rams are willing to spend money on Tackles, but not interior Olinemen. So they have to keep developing late round picks for the interior positions and see what comes of it.
I really doubt they take a RB except as a preferred UDFA.. They have a good RB stable as is. If anything might be helpful, it would be a thumping RB in the 230 + lb range that can get you that 1 to 1 1/2 yards when you must have it and the D knows that's what you're going to do.
The Rams will ALWAYS be looking to guys who affect the passing game on D.