You have two options:
[1] Make sure FTP details are correct. For automatic upgrade, it is required.
[2] If this is a new installation, you can uninstall it from Fanstico and then do a manual installation of latest WordPress version.
You can access it using temporary URL (provided mod_userdir is not enabled on the server) http://174.121.0.253/~yourcpaneluser/wp-admin/
To downgrade the version, you will also require to restore your database from the backup.
