have you tried running the uninstallsql yet? it willnot remove the files but will remove the sql data from your database..

it might be cause you inserted the code out of sequence. but going through myphpadmin it should have been able to take all the code at once in the SQL tab.

and your tables do start with zen_ right?

Also before adding the sql install data again I would manually upload each file thus overwriting the one on the server, sometimes that helps.