1) For this please use this code in your wplms-customizer.php file present in your wplms customizer plugin:
add_action('wplms_course_unit_comment','custom_approve_unit_comments',10,4);
function custom_approve_unit_comments($unit_id,$user_id,$comment_id,$args){
if( 'unit' == get_post_type( $unit_id )) {
$retrieved_comment = get_comment( $comment_id, ARRAY_A );
//approve comment
$commentarr = $retrieved_comment;
$commentarr['comment_ID'] = $comment_id;
$commentarr['comment_approved'] = 1;
wp_update_comment( $commentarr );
}
}
2) For this please go to wp-admin->lms->settings->touch points->unit comment added by user, refer:
http://prntscr.com/bvp3na and enable the email for students.