minifilter design - where do I start?

Hi,

I need to write a minifilter that will provide HSM like functionality.
Specifically, I would like to replace a file with a stub that has a GUID
and maybe a version number. That’s it. When an application requests the
file attributes, times or bits I will provide them.

Where do I start designing something like this? Any insight or tips
would really be helpful. I have been looking at the samples and it
appears that the “scanner” example is a good place to start. Is there a
better example available?

Thanks!

Chris