thanx a lot for your advice. I'll try to find a way to make installation easy, somehow. Improvement on navigation of the install script or something.

To make admin:
Yes, there is NO admin user/pw in user_config.inc.php.
"user" and "password" stuff in user_config.inc.php means "MySQL user" and "MySQL password". You cannot login with this MySQL user id/pw for security reason.

To make "Admin" that can post or edit the entries, you have to login "ACCOUNT MANAGER" with your "MySQL user" and "MySQL password".
then, login again with the "Admin & pw" that you've created.

You don't have to edit ".htaccess". All you have to do is write your "MySQL user name" and "MySQL user pass" in "user_config.inc.php" and create a "Admin user" and "Admin pass" with "MySQL user name & pass".