Who Was That Masked Man?
Sadly, this masking trick does not work with imported QuickTime movies.
The Shapes tool has 15 presets, including a Pen tool for creating custom Bézier shapes. Plus, the shapes can be used to mask graphics. Create a new shape on a slide, and drag any supported graphic file into the selected shape, and drop the image. It’s automatically masked inside of the object, and clicking the image brings up a control panel for scaling the image inside of the shape mask. Double-clicking the image toggles a view that displays a ghosted version of the image beyond the shape boundaries, and you can reposition the masked image using the Hand tool.
Son of Masks
Using a gradient as a mask allows you to have total control over blending with the background.
If you drop bitmapped images into Keynote, you can use the Alpha tool to make a quick mask without switching to an external image-editing app. As expected, objects on solid backgrounds make for the cleanest results. But for potentially problematic images, such as hair or smoke, you can click inside of multiple discontinuous regions, like the background around the phone and the area of the coiled phone cord in the screenshots.
Mergers & Acquisitions
Surprisingly, there’s no way to instantly import an existing Keynote presentation directly into another Keynote document. If you’re working in a group where multiple team members are working on separate, discrete portions of a presentation, you’ll need to open the multiple documents on a single machine, and drag all the slides from one Keynote document into another, dropping them in the Left column of the Navigator view, or into the desired position in the Light Table view.
Presentation Playback
A big part of the impression you make with a presentation is influenced by how it’s played to the audience. You may not need to use any other playback mode beyond the default Normal, but Keynote offers a few other options. Here are some tips for wowing your audience.
Put it On Auto-Pilot 
The “self-playing” option makes your presentation run without you getting in the way.
In the Document subsection of the Document tab of the Inspector, click the pop-up menu for Presentation, and you’ll see a few choices for playback. “Self-playing” is designed for creating slideshows that simply run on their own, perfect for sequencing slideshows for information kiosks, self-contained art shows, or dynamic backdrops for big-screen TVs or projectors at parties or clubs. There are some special techniques to using this mode creatively, as detailed in the three tips that follow.
Know Your Processing Power
Certain transition effects require powerful graphics processors in more recent machines. The Confetti, Blur, and Flash transitions that look great on a MacBook Pro wouldn’t run at all on our PowerBook G4. Keynote automatically disables the transitions that don’t run on the machine a slideshow is running on, so you might need to tweak transition settings on the playback Mac.
Slow Dissolves
We normally recommend using quick transitions between slides and for Builds. But if you’re working with images exclusively, try longer transitions—we love setting Dissolves to last a couple of minutes between full-screen photos. And assigning a text or graphic element the Confetti build-out effect, set to evolve over 20 or 30 seconds, can be captivating
In for The Duration 
Each slide in this self-running presentation is onscreen for 3.5 seconds.
The duration of all slides is automatically set by changing the delay for transitions in the Inspector’s Document panel. If you want a slide to last longer (or shorter) than this global value, you need to select the slide and click the Slide Transition panel, select “automatically” from the “Start Transition” popup menu, and enter the desired duration in the Delay field to the right.
This slide is set to 11.5 seconds, which overrides the global 3.5 second slide duration set in the overall Document panel.
If a QuickTime movie is longer than the duration of its slide (which is set in the Inspector panel for the slide in question), it’ll get cut off by the next slide. You’ll need to increase the time in the duration field for the slide; a slide can be onscreen for 600 seconds (10 minutes) maximum. If your QuickTime movie is longer than that, you’re out of luck. However, the duration factor also depends on the playback computer. If you design a Keynote presentation with lots of movies and tweak the duration so it’s just right, you’ll get a shock when you go to play the presentation on a different, slower computer. To avoid making this discovery in front of your audience, always run your Keynote presentation on the Mac you plan to use for the final presentation.
