Hi,
to answer one of your question out of the blue ( I am currently looking up the rest of your questions).
you can't blend animations made with sprites. by that I mean, the animation will have to stop in order to show a different image, this is not "animations" like in 3d where you can blend bones transform.
So, really wait for the animation to end or just display the new animation. OR create in between animations to "transit" from one animation to the other.
Does that make sense?
Bye,
Jean