When you put in the included SQL, how did you do it? I've seen this problem come up and this question asked on just about every contrib support forum out there :) I don't know how table prefixes work because mine don't use them (I don't understand why anyone's do)... but the answer always seems to be "input the SQL into phpmyadmin, NOT the SQL tool in your Zen admin!"

Good luck. I'm pretty sure its not a problem with this contrib though.

- Steven