hi,
thanks a lot for this great tutorial 
you brought it clear to the point and it´s a joy to learn from it. after searching for this effect i finally got it in game and thanks for the metahuman animation tip, works like a charm. the only weird thing was, i first took the new skeleton from u5 and retarget it to u4, but this messes up the animation. then i tried using u4 skeleton straight and it works without any problems 
many thanks!
cheers