Can u add more details? is this a custom report with sql or have you done using only the wizard?
do you have the crm server and sql server on the same box?
not showing anything is usually a problem with crm server contacting the sql report server. I could be account related, the account that runs the crm app pool or could be an issue with the crm sql report adapter
can you run the report straight from sql report server?
I Hope I could help. If I have answered please mark as 'Answer'. If was just helpful, please vote. Thanks and happy coding!