Chapter 1 during the moment we talk about a little thing broken on ground we must answer how he finish on ground I answer a bad answer and after that he completly change the choice to return on when the victim is dead (therefore at the beginning of the trial).
Chapter 2 we must answer about what kill the victim (the weapon) but after that good answer he skips a big part and talk like "the paper we talk earlier" but during the trial I never talk about the paper and therefore I finish by argument against the culprit without do all the trial.
Sorry if it's difficult to understand. for more detail I made the video on youtube (my channel is Hibouette) :
the first bug it's on this video Jikoronpa : Chapitre 1 : 1ère lamentation : Aimer plutôt l'Oiseau-Tonnerre. (Partie 3)
in this time code : 2:40:00
the second bug it's on this video : Jikoronpa : Chapitre 2 : 2e lamentation : Promise à la mort, les billes en porte la rime. (Partie 3)
in this time code : 1:08:50
Sorry for my bad english I try my best to be understood. My version of this game it's the 5.3