You'll need to do some scripting for this.
http://i.imgur.com/kqtLBcS.png
If you haven't already you'll want to make a new keyboard map (don't use the default). It's the button right beside the keyboard map dropdown.
And you can assign any keyboard shortcut to these actions.
And then use a script like this:
dim output as xpoutputFramebuffer
dim scene as xpScene
dim dir as xpSceneDirector
engine.Getoutputframebuffer(0, output)
output.GetSceneonlayer(0, scene)
scene.GetSceneDirectorByName("Refresh", dir)
dir.playrange(0, 200)
That'll trigger a scenedirector by name on a certain output and layer.
If you want to trigger just an animation controller you would use the 'GetAnimControllerByName' instead.
You can find the different methods (play, stop, pause, etc) you can apply to the SceneDirectors and AnimationControllers in the XPression SDK file under the xpSceneDirector Object Members and xpAnimationController Object Members.
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