First, you will want to make sure that you install Management Reporter under a domain account as opposed to a local system or network service account. Management Reporter gives you the option to install under these accounts, but it is a be a best practice approach to use a domain account.

Upon installation of Management Report, you will want to make sure that Directory Browsing is enabled within the IIS server of your site or you will have problems when you go to use Management Reporter. By default, it will be disabled in Server 2008 R2 and you will need to make the setting change under the Actions pane shown below.

Lastly, you will want to make sure that SQL Server is running under a domain account. I have had multiple situations where reports have been stuck in the Queued status rather than Processing status of Management Reporter. After reviewing resolution 5 of KB 2298248, it was determined that running SQL Server under a domain account is the way to go.