Who to contact for FastCGI support?

I recently opened a support ticket with Microsoft Product Support Services for an issue with slow WordPress sites.  The only thing that they told us was that the slowness arises somewhere in the FastCGIModule, which is very non-specific.  At that point we were told that Microsoft cannot support or further troubleshoot the FastCGIModule.

Who do I go to for support on this?

Hobbes