Following a number of questions posted in the Community Q&A area this article attempts to answer why the keyboard and search boxes don't work in the Zmags viewer when you switch to full-screen mode.
Having looked through a number of articles on the Adobe Help Portal this is due to a limitation with Flash Player. Flash Player 10 enabled the use of the following keys; Tab, Spacebar and the Arrow Keys (up, down, left, right) however the rest of the keyboard is still restricted.
This is therefore not an issue with the publication using Flash, or the options available with the Viewer but it is something that requires Adobe to update Flash Player.