Launch analysis board using the current board position as the start position, and the following moves from the current position as the initial analysis move list. If you want all the board moves to be loaded into the analysis board then use the Jump to Start button before clicking the launch analysis board button. See the Analysis Board section of the manual for more details.
The Copy FEN button allows you to view and copy the FEN description of the current position, which can then be pasted into other applications, or other parts of the Chess Tempo site that accept FEN strings as input. The dialog which shows the FEN, will also show a 'copy to comment' button, it is relevant to the context. The 'copy to comment' button allows you to create a static image of the current board position in a comment.