[john.gersh]

I've done some interactive mockups using jump-to-canvas actions. Nothing's animated, of course, but as Brian said, you can click a pop-up icon, see the menu appear, then click a menu item and go to a new screen and so forth.

That's fairly easy to do for demoing a few threads through a mockup. If you want to make it fully interactive, though, you need a separate canvas for each state of each screen you want to access. It's not hard to build the canvases using shared layers (Pro version), but it can get pretty complicated to keep track of them and of the actions implementing all the transition paths you want to exercise.

OG added show/hide layers actions in OG 5, which does make some things easier. It's also nice that you can, with some limitations, export your mockup to a linked set of HTML image maps or to a pdf with internal links; you don't need OG to run the mockup.

Given all that, OG is fine for designing or demoing a relatively simple set of interactions. There are better solutions for more extensive tasks, like usability testing of complex apps on a regular basis.