So this error happened when you started a new game, but not when you continued a saved game?
Well, I'm not a scripter and I'm not sure what the problem is, since I obviously don't know what's exactly at that line, but the best thing to check is the scripts. If you tampered with an existing script for the scrolling text you tried but didn't like, try reloading the default script from a new game for it, as well as the entire Game_Character 1 script. Probably won't help, but it's worth a shot until a person who actually knows how the scripts work sees this.