not sure what you were doing with the pose..unless I misunderstood you wanted the effect to flow from one end to the other of the model which the way it was set up I assume was bottom to top so only the Y direction had to be modified in the pose changing the start and end values of the gradient material I embedded the material and models into a project after I did the positions in the gradient for when the pose was 0 and then at 100 check and see what I did then ask if you have any further questions
results ..model shown twice once flipped
fix.mov
fixed.zip