The box is there to protect the plastic bag inside of it. I've seen them in shops. If you're really concerned just shake it before using. Personally I wouldn't care about it since its 6 gallons of oil and not a 1 quart bottle. You may damage it by rolling it if you go that route..
As long as it does not freeze, the likelihood of any of the chemistry separating is very unlikely. The add-pak arrives at the blender as an oil and goes right into the mix of base oils. Unless it's an Ester oil, it should be fine