As Sreekanth points out, Responsive Projects are HTML5 output only, which means that you cannot use an SWF's in it. Everything that is greyed out for Responsive projects is not available for them: all objects that are indicated by the HTML tracker, line shape, freeform polygon shape and custom shape, D&D. This has nothing to do with being on Mac/Win, why do Mac users feel mostly discriminated I don't understand at all. Have a look at the Help documentation, where you can find everything that is not supported (yet) for Responsive projects. If you want an animation, you can use an Effect (those who are supported, they are indicated in the Effects panel) or create a HMTL/Edge animation and insert that.