Contains will funnel outside runs back inside. Try picking a 3-4 defense with the line in contain from the playbook. Now shift your lbs to the offenses strong-side. And shift the dline in the opposite direction. User the LB on the opposite side YOU THINK the outside run is going for containment. Take that to the lab.....
As far as NANOS go.....are you sure you aren't confusing OVERLOADS with NANOS? They are far from being the samething......