1. in config.php delete these sections: Kyvio Settings, Aweber Settings and Get Response Settings (the ones marked by the red curly brace)
    https://i.imgur.com/hV8B0OT.jpg
2. Add the following line in config.php: (anywhere inside there as long as it's a new line)
    $form_action = "https://em.fluttermail.com/proc.php";

3. in the upload_files.zip you have the main index.php (not the one from thank-you folder)
    Search for this string: "<form"
    https://i.imgur.com/Mc01boh.jpg
    Somewhere bellow there you have name="name"
    Replace name="name" with name="fullname"

4.Somewhere bellow you must delete the following:
        <input name="listname" value="<?php echo $listname; ?>" type="hidden">
        <input name="redirect" value="<?php echo $redirect; ?>" type="hidden">
        <input name="thankyou_url" value="<?php echo $thankyou_url; ?>" type="hidden">
        <input name="optin_id" value="<?php echo $optin_id; ?>" type="hidden">
        <input name="mailist_id" value="<?php echo $mailist_id; ?>" type="hidden">
        <input name="campaign_token" value="<?php echo $campaign_token; ?>" type="hidden">
4. add these in place of the ones you deleted:
        <input name="f" value="153731" type="hidden">
        <input name="s" value="" type="hidden">
        <input name="c" value="0" type="hidden">
        <input name="m" value="0" type="hidden">
        <input name="act" value="sub" type="hidden">
        <input name="nlbox[]" value="11200" type="hidden">