The user needs all permissions to create db objects. And permissions are specific by which host the user is connected from unless the permissions are granted for username@any
You did not say what steps you took to do a "manual" installation, so I'm not convinced it was done correctly. Also if you create the tables with a different user than the one in your connection string then there may not be correct permissions. Currently your system is in an unknown state and that makes it very difficult to help.
I recommend clean all objects out fo the db and resolve the connection string permission problem then use the automated setup.
If you are using MySql 5.1, I'm sorry but its buggy and was released with bugs, 5.0 is the version I recommend for production dbs. I have never been able to install mojoPortal on MySql 5.1.
Hope it helps,