1)What kind of official channel for feedback you refer?
2)Try
www.urlrewriting.net with iis7 in "DefaultPool"=native mode.+some
simple sitemap,after that reverse to "Classic .NET App pool" and see
the difference.
In web.sitemap you set [/siteMapNode/@url] to "clear" path used in you
application-before urlrewriting module rewrite it to internal .aspx or
something.
In "native" mode sitemap framework see already rewrited url,not url
used in you app-that's the problem.
If you have any more questions,please let me know.
Thanks.