Here are the classes, structs, unions and interfaces with brief descriptions:

CAsymptoticExclusion
CCombinedParameter
CCombinedProfileLikelihood
CdataHandler
CerrorHandler	Helper Class to send consistently formatted messages. It allows different levels of severity for the messages: Info, Warning and Error
ChistoCompare	This class is supposed to compare a "base" histo with a set of other histogram. One can choose for ratio plot, stack plot of different component, one can set the projected axis and the slice on which do the projection, one can also rebin the histo. the histo are supposed to be TH2F
CLikelihood
CLKParameter
CpdfComponent
CpdfLikelihood	Implements 2D pdf profiled likelihood fitting
CprintTools	Printing helpers, probably you wont use this class
CProfileLikelihood
CscaleSys
CshapeSys	It represents a Shape Systematic. It inherits from LKParameter. Here you can use the LKParameter functions to set initial val, min, max and setp
CSigmaParameter
CTEfficiencyParameter
CTGaussParameter
CTLEffParameter
CToyFitterExclusion	Class to handle the fitting of toy dataset for limit production
CToyGenerator	Helper class to generate toys given an input likelihood. It can generate toys for the calibration dataset and for the "science data" dataset
CTQyParameter
CTStatBkgParameter
CTSystBkgParameter
CXeStat
CXeVersion