The Installation guide has some important changes regarding the machine keys.

One thing that didn't make it in this release is a flaw in this document!!

Rename your old web.config to web.backup.resources instead of web.config.backup

In case you are wondering why, the resources extension is a protected extension in asp.net so nobody can actually download it !!!

Please, please make this known to the entire community, I would hate to see someone download your web.config.backup..