Missouri RB Cody Schrader is one of the players the Lions reportedly had a Pre-Draft visit with the Lions. Of the 18 players as of now that have had confirmed Pre-Draft visit with the Lions or reportedly had a visit, Schrader is the only player who primarily is a RB. Utah S Sione Vaki has been used as a RB.
It's hard to envision the Lions drafting a RB before the Lions are scheduled to be on the clock with Pick # 164, in Round 5.
For the Lions to draft a RB from that point on, Special Teams production and potential probably would be key criteria. Versatility, in addition to Special Teams, would certainly help the chances of the Lions to draft a RB with those skills.