Keynote movie playback ignores start/stop times, only in presentation mode I'm putting together a presentation in Keynote '09.  I've embedded a movie (created by exporting a keynote slide, so that I can continuously loop the animations).  I'd like to skip the beginning and end of the movie, since there are undesirable acceleration/decelerations in the animation.  I've gone into the Quicktime tab of the Inspector window, and set the start and stop points appropriately

|----------1-------------------2-----------|
           ^                   ^
    desired start       desired stop


When I hit 'Play' in the inspector, it works great.  When I double-click the slide in edit mode, it works great.  When I go into presentation mode, it doesn't work.

|----------1-------------------2-----------|
           ^                               ^
    loop 1 start                    loop 1 end

^                                          ^
loop 2 start                        loop 2 end


What's going on here?  Is there a way to avoid this behavior?
Since you have set start and end on the clip, Keynote can permanently clip it after reducing file size to save space and improve performance.  The result is that the undesired parts of the clips are no longer even available to Keynote so they shouldn't play when looping.


Set your start and end points
Go to File > Advanced > Reduce File Size


Keynote will trim the excess footage from your video file.  You will note the change if you deselect the video then select again and view the Edit Movie in the inspector.  (Be sure you keep the original somewhere else as a backup.)

Before:



After: