Hi !
I'm a bit lazy so I'll just post the code that infers track folders 
Code:
public static string GetTrackFolderName(TrackNameWipeout name, TrackClassWipeout @class)
{
if (name == TrackNameWipeout.AltimaVII && @class == TrackClassWipeout.Venom) return "TRACK02";
if (name == TrackNameWipeout.AltimaVII && @class == TrackClassWipeout.Rapier) return "TRACK03";
if (name == TrackNameWipeout.KarbonisV && @class == TrackClassWipeout.Venom) return "TRACK04";
if (name == TrackNameWipeout.KarbonisV && @class == TrackClassWipeout.Rapier) return "TRACK05";
if (name == TrackNameWipeout.Terramax && @class == TrackClassWipeout.Venom) return "TRACK01";
if (name == TrackNameWipeout.Terramax && @class == TrackClassWipeout.Rapier) return "TRACK06";
if (name == TrackNameWipeout.Korodera && @class == TrackClassWipeout.Venom) return "TRACK12";
if (name == TrackNameWipeout.Korodera && @class == TrackClassWipeout.Rapier) return "TRACK07";
if (name == TrackNameWipeout.ArridosIV && @class == TrackClassWipeout.Venom) return "TRACK08";
if (name == TrackNameWipeout.ArridosIV && @class == TrackClassWipeout.Rapier) return "TRACK11";
if (name == TrackNameWipeout.Silverstream && @class == TrackClassWipeout.Venom) return "TRACK09";
if (name == TrackNameWipeout.Silverstream && @class == TrackClassWipeout.Rapier) return "TRACK13";
if (name == TrackNameWipeout.Firestar && @class == TrackClassWipeout.Venom) return "TRACK10";
if (name == TrackNameWipeout.Firestar && @class == TrackClassWipeout.Rapier) return "TRACK14";
if (name == TrackNameWipeout.Track15) return "TRACK15";
throw new ArgumentOutOfRangeException();
}
IIRC Track15 is the beta of Arridos or Terramax ...