Found 'em!
Compare an actual photo of the stage of the Cedar Point convention (from Pay Attention to Daniel's Prophecy, page 299) with the re-enactment from the DVD: Jehovah's Witnesses - Faith In Action, Part 1.
You will notice that at the actual convention, the hall and stage were framed by the US star spangled banner flag. Yet this detail has been left out from the DVD.
Notice how this is "explained" by the WTBTS in the the 2011 Yearbook under the heading "Tracing All Things With Accuracy":
In summary, the Writing Department insists on using only material that is accurate and truthful, even regarding seemingly insignificant details. As a result, "the faithful and discreet slave" can consistently supply spiritual food that brings honor to "the God of truth".
As JWFacts commented in his thread, Watchtower falsification of its history:
This is not an insignificant detail but a major prophetic and doctrinal issue. The 1922 Cedar Point convention is supposedly a "landmark convention" that was fulfilment of Daniel and Revelation prophecy. It is the end of the 1290 days from Daniel 12 and beginning of the 1335 days, as well as signifying commencement of the pouring out of the seven bowls of God's anger.
Things that make you go, "Hmmmm!"