I just finsihed doing the exact same thing you are discussing. I did the web testing exactly as Shonky suggested. Your message seems to indicate an issue importing the tables though, and this would be on the mysql host.
First, I didn't have problems accessing my new mysqlhost name as long as I started phpMyAdmin from my dreamhost panel. Second, your mysql hostnames all actually point to the same location, so you could connect to the host using a different hostname (from an existing domain) and just connect to the desired database from there.
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