error while running install.sql in community auth

I am trying to create a user. But I am getting an error

A Database Error Occurred
Error Number: 1054
Unknown column 'user_id' in 'where clause'
SELECT * FROM `users` WHERE `user_id` = 2147484848
Filename: C:/xampp/htdocs/sub_crud2/system/database/DB_driver.php
Line Number: 691

I think that this is due to the fact that I already had a table called users, so when I ran sql.ini the script didn't create the users table that Community Auth needs, because there is an already existing users table (with different field names). How do you recommend to resolve this? I can modify sql.ini to create table users2, but then I will need to modify the community auth code, all over. And I don't want to make my system so I have a "custom version" of Community Auth.

proof that an old dog can learn new tricks