Actually, I have tried it several times, with several users:
1. First time, I've created a MySQL user named "ispconfig" with all root privileges. SQL dump error.
2. Second time, I've copied the "root" user via PHPMyAdmin, with the host modified from "localhost" to the IP address of the ISPConfig host, so I have two root accounts (one is the original, new is for ISPConfig). Same error.
None of these approaches worked beyond correctly logging in and creating the "dbispconfig" database. They all stop with the SQL dump error. I've always deleted the database and flushed privileges before trying again.
I'm out of options. Any suggestions?