Dissidia 012: Duodecim Final Fantasy

[1Timestones]

Ahhh...wrong symbol name.
You can't change battle setup in story mode. You can pick the oppents starting equipment and bgm before a fight, that is it.
You load your game. You should have a list with story mode, battle mode, pp (catolage), that is likely speled wrong, data config, etc. Cick batte mode, quick battle. Pick the char you want to play, then your foe, then arena. And see if it loads that way.
If it does, you could try telling the game to skip all cutscenes. It always dropped me when I playing Kains's chapter. SoI told the game to skip them, then I had no issues with arenas in story mode.

Otherwise, I don't have any suggestions.