An event which is raised just before the XLL's add-in functions are registered.
class CXlRegisterFunctionsEvent : public CXlEvent
The event occurs just before the XLL's add-in functions are registered. This usually occurs when the XLL is opened, after the CXllOpenEvent.
Observers should register for this event early in the life of the XLL. Registration can be done explicitly during CXllApp::InitInstance, or automatically by creating an instance of CXlRegisterFunctionsEventStaticObserver.