This problem started on 2.32, it did not happened on
previous versions.

When the armature deformation depends on the
transformations on an external object, that in turn is
been affected by a second external object, the starting
armature is not up-dating itself on the 3D window, but
shows right on the render.. it makes the animation task
quite up-hill to do a change and render to see the efect.

The companion .blend file contains more detailed
description and the single step needed to duplicate the
error.

(Just in case, the same .blend will be available at
http://www.freewebz.com/apollux/Cook.blend for the time
been)