Néstor Romeral Andrés
The rules specify that you can optionally place the unused pieces (from a game with fewer than 5 players) on the board to create dead spaces. Can the Great Dragon be used to swap a piece with one of these neutral pieces on the same track, or does "they are not moved during the game" mean you can't swap them, either? (Since it's been established that you're allowed to swap a piece on a numbered space, I assume you can swap a neutral piece, too.)
It hasn't been established for certain yet whether you're allowed to swap a piece that hasn't entered the board yet with a piece that's on the board, although I suspect not.
Correct. You can't swap them