Chances are your databases are not setup correctly. Make sure that for these they are something like

<login>your-cpanel-username_the-name-you-gave-your-db-username</login>
<password>the-name-you-gave-your-db-password</password>
<default>your-cpanel-username_the-name-you-gave-your-database</default>

When you imported the db.sql file into phpMyAdmin that was coping the tables to the database. phpMyAdmin is a database managing utility, when you view your database in that you should see all of the tables listed on the left, if you don't then you didn't import them.

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