The Apache module doesn't support S/SHA512, you'll have to reset the password of your admin user to use MD5. The roundcube password changing plugin by default sets them in MD5 so you should be able to use that.

There's probably a better way to get an MD5 hash but the only way I can think of right now is the command:

doveadm pw -sMD5

It'll ask you for your password twice after which just copy the output into the corresponding user's MySQL Mailbox entry. Sorry about this issue, one of the many reasons iRedMail is dropping Apache support, while it'll still work with it, it won't get support, and NGinX will be encouraged.

Let me know if the above works for you

Are you using a Global Admin for this? Looking at the cluebringer.conf file it only allows Global Admins to log into the interface

Have you seen this?
www.iredmail.org/forum/topic7094-iredmail-support-cannot-authenticate-to-cluebringer-or-awstats.html
there's a few things in there you could try

Reinstalled iredmail using ldap - no more problems accessing cluebringer / awstats.