How to use IIS 7 custom logging module and ETW tracing module

Question

Hi, I notice that IIS 7 has a custom logging module logcust.dll. It is said this module helps load your own custom logging module. But I can't find any information about how to use it. I opened this DLL and notice that it implements IHttpModule and register to all events but does nothing in event handlers.

Same question for another IIS ETW Module iisetw.dll.