Version 5.1.7 - Errors: 404 and custom ratings

I use wpDiscuz on 7 sites, but starting with version 5.1.7 I have two issues on all these sites, hosted on various hostings.

1. With "Enable WordPress native ajax" disabled, the comment is not published.

Error in web browsers:

POST https://********** /wp-content/plugins/wpdiscuz/utils/ajax/wpdiscuz-ajax.php 404
send @ jquery.js?ver=1.12.4:4
ajax @ jquery.js?ver=1.12.4:4
getCustomAjaxObj @ wpdiscuz.js?ver=5.1.7:1438
(anonymous) @ wpdiscuz.js?ver=5.1.7:289

Error in Cpanel:

AH01630: client denied by server configuration: /home//***/wp-content/plugins/wpdiscuz/utils/ajax/wpdiscuz-ajax.php

2. With "Enable WordPress native ajax" enabled, the comment is published, but custom ratings are not sent to the database, and the comment is displayed without custom ratings. If I edit the comment from wp-admin and add a fake rating from admin, the rating is displayed.

In previous versions of Wpdiscuz, I did not have these errors.