Zimbra setup stopping its setup on "zimbra-spell" can also be a problem with the DNS, no FQDN for the server. You should double check that.
See that thread :
fresh install (both OS and Zimbra) but zimbra-spell fails
Don't forget a full clean uninstall before lauching the install script again.
(Yes, I had the very same issue and did not clean before trying again 8))