re: Scheme might be an issue, but here is what I noticed after seeing film

Boxing and spilling are ways you take on blocks, not tackling technique. I think you are excited that you know some football terms. If you are a box team or you a going to box a block, the defender takes on the blocker with his inside arm and foot up and the object is to force the ball carrier to cut back inside. The box players job is to not let anything outside of him. If you are a spill player or spilling a block, you are doing the exact opposite, you are taking on the inside part of the blocker, and forcing the ball carrier to the outside, or to bounce the ball outside. I just want to reiterate, that I am talking about tackling the ball carrier when I say inside and in front, not taking on blockers or how to play certain runs.