Were you able to load the v5 database into v6.2 using the existing AES256 encryption method?
I have a v5 database that I've upgraded to v6.2, but when I try to set the ""Default Encryption Scheme"" on the new v6.2 app server to match the old v5 app server's ""Credential Key"" I get an error that the key is not valid. Did you run into this issue?