I bought the game, at the end in the temple I checked and it says that I have the purchased version I don't have the trailer for the free version :)
Hi, I just finished it, and think maybe that "file 8" is meant to be blank? I have played the others, which "khywae's boat" is always at the last file (even with some previous blank files - which awaiting my selection of other choices for them to appear), so since for Toji's, boat is at "file 7", that should be the end; maybe khywae just somehow set one additional save slot that is not used for this game, ^ ^