Hi Rohit,
If you are connecting from Personas source system to different target system then clientaccesspolicy.xml and crossdomain.xml needs to be setup correctly (files should be directly under server root folder) on target system. If source and target systems are same, then it is not mandatory.
Thanks for confirming on the role. As I mentioned, if you are using Personas 2.0 SP2 then please ask your Basis team to apply note#2016378 as well.
If you are still facing issue, then I would suggest you to log a message to BC-PER-DT component and provide HTTP, R3 access to your source and target systems along with logon credentials.
Regards
Chinthan