Running latest Sierra public beta.
Tried to launch all three apps from my iWork '09 folder.
All launched fine, and could show a new document, as well as open older docs.
I don't actively use '09, other than every few months with Keynote '09, which does not fail me.
I also have the updated Pages/Numbers/Keynote, but continue to keep the old iWorks folder, as long as the apps continue to launch, and on the off-chance that some file will show up that I need to edit with Keynote, and won't open with the latest version Keynote. (I support a couple of different churches who rely on Macs, and I am their primary support guy. One church cannot afford to upgrade to a Mac that will support newer versions, and is stuck with a PPC mini, hence the need for older software support...
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