@logaritym,

Please read my answers below:

1. On my Lifter LMS lessons commenting, the ADD AN IMAGE button does not appear:

Please note the default "Attach an image" button is only available for the post, pages, and attachments post types, and for default WordPress user roles. For custom post types and custom user roles, the button is not accessible. For more advanced features, we recommend to check out the wpDiscuz Media Uploader add-on.

2. We can't switch our ratings for the articles:(

Please read this doc: https://wpdiscuz.com/docs/wpdiscuz-7/getting-started/manage-comment-forms/comment-form-settings/#enable-post-rating

3. When I disable the FOLLOW USER feature, it still appears as a tab in MY CONTENT AND SETTINGS.

Navigate to Dashboard > wpDiscuz > Settings > User Authorization and Profile Data tab, and configure the settings for the "My Content and Settings" button. More info here: https://wpdiscuz.com/docs/wpdiscuz-7/plugin-settings/user-authorization-and-profile-data/#%E2%80%9Cmy-content-and-settings%E2%80%9D-button

4. I don't think "Be the First to Comment!" should be capitalized. It looks like a regular sentence with an exclamation mark at the end...

Please navigate to Dashboard > wpDiscuz > Phrases > General tab and change the value of the phrase as you like. 

When I hover over some of the formatting buttons, the ovals do not highlight (perfectly) symmetrically around the icons inside.

This is just a small CSS conflict with the active theme, use this CSS code to solve it: 

#wpdcom .ql-toolbar button:hover {
   border-radius: 0;
   background-color: unset !important;
   box-shadow:none !important;
}

Put the code in the Top Admin Bar > Customize > Additional CSS > "Additional CSS" textarea, save it, delete all caches and check again. 

Please don't forget to press Ctrl+F5 (twice) on the frontend before checking.

Also, I'm not sure why there is a Google sign on top of my avatar in the comments and how to remove it.

Navigate to Dashboard > wpDiscuz > Settings > Social Login and Share admin page and disable the "Display Social Network Icon on User Avatars" option. 

@logaritym,

Currently, there is no integration with BuddyBoss. However, this is already in our to-do list. We're planning to add BuddyBoss integration addon in the future.