There is a new attribute called MUIA_Application_UsedClasses in the new alpha/beta MUI V20.
Its argument is a pointer to structure of string arrays that are in fact names of mcc's used in program.
I wonder if does it make sense to put there BetterBallance.mcc while it has no settings provided for end user.
Also in main MUI prefs, after clicking on "Show MCC's" it don't list it.