Before we go on with the actual code, we need to finish up a few things first so that the code actually knows there is a new update_HETR function. Go back to powder.h at line ~ 250. You will see lots of int update_'(UPDATE_FUNC_ARGS); . This list is sorted alphabetically so lets put in our new HETR function.
int update_RANB(UPDATE_FUNC_ARGS);