The review status lets you set the clip to a certain status. Go to the player for a clip in the share (see Review shared clips). At the top left, at the bottom right of the coloured header, you'll find the review status:
Click the status and a menu will appear with possible statuses. Select one in the menu to change the clip status.
It's possible the statuses you see are different from the image above, as the statuses can be specific to the production.
It's important to note that there is only one review status for the clip. If you approve it, the clip is approved for everyone viewing the clip.
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