Sorry if I'm responding just now. I'm very sorry about this. I'm looking for a solution to this problem. Basically, for what I'm reading online, to play this kind of game, made with RPGMaker XP, you have to download and install RPGMXP. Now I've found another way to include the data in the game. I'm uploading a new version of the game that hopefully will work even if you don't have RPGmaker XP installed.
Again, sorry about this, and thank you so much for telling me about this.