INPUTS

base
= if you create a public class, you have to call MUI_CreateCustomClass() from your libraries init function. In this case, place your library base pointer here. For private classes, you must supply NULL.

supername
= super class of your class. This can either be a builtin MUI class (''xyz.mui'') or a external custom class (''xyz.mcc'').

supermcc
= if (and only if) the super class is a private custom class and hence has no name, you are allowed to pass a NULL supername and a pointer to the MUI_CustomClass structure of the super class here.

datasize
= size of your classes data structure.

dispfunc
= your classes dispatcher function (no hook!). The dispatcher will be called with a struct IClass in a0, with your object in a2 and the message in a1.