Hi All,
How large is the account that you are attempting to download performance data for? I was successfull in downloading performace stats for I can confirm that in the next version of the editor (Ace v2) that you can select the same options that are also available through the regular adCenter web interface.
If you are having any missing data with the current version of Ace (v1), you can select the range you are wanting to see and click the Refresh button below your selction from the main ribbon.
Thank you,
Brian H - MSFT