plauk, if you verify the named-ness of all the objects, and it still doesn't work, please send me the project at lucid@brashmonkey.com, and I'll take a look.
Also, note, all objects on all animations must be named. If you want an object to use the same c2 sprite object across animations, give it the same name in all animations.
Once again, when the next version of Spriter releases this will all be automated, and you'll only have to change names if you don't want the default name, or if you want to avoid using the same c2 object across animations for some reason