So when you creating plugin and there is admin page for your plugin you can get error You do not have sufficient permissions to access this page . This is easy to fix: in your plugin file  you have such code:

add_action('admin_menu', 'rotator_bar_admin_actions');
 function rotator_bar_admin_actions() {
 add_options_page("WP Rotator Bar", "WP Rotator Bar", 'read', "rotator-bar", "rotator_bar_admin");
}

so 4th option for function add_options_page should be the same name as your main plugin file for example my one is rotator-bar.php, if you have different name there you will get error above