Error with Report Builder

After I installed the latest version of report builder and tried to setup the RDS to my CF 8 server I received an error 404 not found. After searching on the web I discovered that I needed to add a new folder in cfide called 'main' and put a blank cfm file called 'ide.cfm' now when trying to test an RDS connection I recieve this error:

Object: TfrmConfigureHSRDS, frmConfigureHSRDS_1
Exception:List index out of bounds (2)
See error log for stack trace

Any idea what might be causing this, I seem to be able to connect to another CF server (7.02) without any issues.

Thanks