Is the EEFF 4.1 extension backward compatible with EEFF 4.0? We would like to test 4.1 first before upgrading client PCs, but there is no "evaluation" extension branch like for the software packages. In general, is it the case that newer product extensions are backward compatible with the previous version software package? Also the 4.1 migration guide says "For a user to open an encrypted file or folder after upgrade, the encryption keys must be imported into McAfee ePO server and assigned through policies." Does this mean that existing policies and keys will need to be reassigned after the upgrade? Thanks.