Notice: Undefined variable

Hello, I just install the plugin with WordPress DEBUG mode enabled and it spawned me this notice:
Notice: Undefined variable: icwp_aMainOptions in [...]/wp-content/plugins/wp-simple-firewall/views/icwp-wpsf-config_header.php
lines: 5,6,7,8,9,10,11 :

$sPluginName = 'WordPress Simple Firewall';
$fAdminAccessOn = $icwp_aMainOptions['enable_admin_access_restriction'] == 'Y';
$fFirewallOn = $icwp_aMainOptions['enable_firewall'] == 'Y';
$fLoginProtectOn = $icwp_aMainOptions['enable_login_protect'] == 'Y';
$fCommentsFilteringOn = $icwp_aMainOptions['enable_comments_filter'] == 'Y';
$fLockdownOn = $icwp_aMainOptions['enable_lockdown'] == 'Y';
$fAutoupdatesOn = $icwp_aMainOptions['enable_autoupdates'] == 'Y';

https://wordpress.org/plugins/wp-simple-firewall/