Well I’ve been having a lot of fun trying to get this installed. For anyone else wondering why the option to install it is greyed out. I’ve discovered that you need the folling installed on the 2008 R2 box:

The most trouble is caused by IIS, and the fact that you need the following bits and pieces in order to make it work.

Component Folder
Static Content Common HTTP Features
Default Document Common HTTP Features
HTTP Redirection Common HTTP Features
Directory Browsing Common HTTP Features
ASP.Net Application Development
ISAPI Extension Application Development
ISAPI Filters Application Development
Windows Authentication Security
IIS Metabase Management Tools
IIS 6 WMI Management Tools

Hopefully, when you have those installed everything should work ok and it will no longer be greyed out. Don’t forget to put SQL SP3 on afterwards!

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