Crystal Report Server XI R2 Auditing

Hi all experts,

Our environment is running Report Server XI R2. We have a requirement to understand the report usage, access statistic etc.

1. How can i achieve to get the report usage statistic ?

2. Is it require auditing function enable ? How to do that ?

3. I checked on my server licenses but it said my "license does not allow auditing"

4. I found there are some sample auditing reports for Crystal Report Server 2008, does any similar sample reports for Report Server XI R2 ?