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.
|Static Content||Common HTTP Features|
|Default Document||Common HTTP Features|
|HTTP Redirection||Common HTTP Features|
|Directory Browsing||Common HTTP Features|
|ISAPI Extension||Application Development|
|ISAPI Filters||Application Development|
|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!