Directors are important creatives along with writers too. Unfortunately Lee has too much influence over Frozen and the product suffers from her lack of talent.
Actors are bodies. While they can bring in a little bit of creativity, they aren't making something new. They are hired for their dynamic abilities (usually), not for their minds. Their performance has a creative element, but they are not breaking ground. If acting is considered a creative work, then couldn't something like truck driving be considered creative pursuits as well? Drivers have a path to follow like actors have to keep to a script but have some room for creative liberties like how actors may choose different deliveries of lines.
I think of creative work as something that can be recreated by other people like sheet music, recipes, choreography, blueprints, & paintings. If you are just reciting what somebody else has created, are you really being creative? It is still hard to draw the lines for what constitutes creation, though for now I suppose if the work is primarily new & original and not just a reiteration in your voice (like adding a spice to a dish), then it is a creative work.