The override command overrides the end action of a timeline asset. unfortunately, there is no way to prevent a chapter from going one to the next within a timeline (well, i say that, but you can set up web links at chapter markers and some other scripting....but for the purposes of encore, you have to just deal with the chapter-to-chapter video flow). think of it this way...there is no end action to override in a chapter because chapters don't "end"....instead, the next chapter just begins. subtle difference (if any) i know, but that's how i remind myself about it when i'm working. maybe it'll help you too
essentially, if you have 2 timelines, with timeline #1 set to "End Action=Timeline #2", then when a user selects timeline #1 timeline #2 will play. timeline #2 end action is probably set to return to the chapter or off to some other asset. when you set up a "Play All" button or similar, you set the button override to return to the menu or do something OTHER THAN the end action set for the timeline #1. does that make sense?
if you go back and chop your video into seperate timelines, you will be able to do this. just create multiple timelines and import the video into each one, then clip front/back to give the impression of multiple clips with only one asset
follow this link for a great (better) explanation of the override function (labeled "The Override Command Explained!":
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