I've uploaded example Flashdevelop project where is shown how to get nested timeline animation under Starling. https://github.com/Oldes/Starling-timeline-example
It's a little bit complicated as it mixes several tools like REBOL (www.rebol.com), xJSFL (www.xjsfl.com), TexturePacker (http://code.google.com/p/libgdx/wiki/TexturePacker) and of course Starling:)
Maybe someone find it inspiring. It's just far to be finished. The main missing part is handling context loss and proper disposing.