Using cachify plugin with BPS together

Hi again
I would like to use cachify plugin for hdd cache together with BPS . The cachify requires some additional code for htaccess:
https://github.com/pluginkollektiv/cachify/wiki/en-Cache-Methods#hard-disk-hdd-cache

# BEGINN CACHIFY
<IfModule mod_rewrite.c>
    # ENGINE ON
    RewriteEngine On

    # GZIP FILE
    <IfModule mod_mime.c>
        RewriteCond %{REQUEST_URI} /$
        RewriteCond %{REQUEST_URI} !^/(wp-admin|wp-content/cache)/.*
        RewriteCond %{REQUEST_METHOD} !=POST
        RewriteCond %{QUERY_STRING} =""
        RewriteCond %{HTTP_COOKIE} !(wp-postpass|wordpress_logged_in|comment_author)_
        RewriteCond %{HTTP:Accept-Encoding} gzip
        RewriteCond %{DOCUMENT_ROOT}/path to/wp-content/cache/cachify/%{HTTP_HOST}%{REQUEST_URI}index.html.gz -f
        RewriteRule ^(.*) /path to/wp-content/cache/cachify/%{HTTP_HOST}%{REQUEST_URI}index.html.gz [L]

        AddType text/html .gz
        AddEncoding gzip .gz
    </IfModule>

    # HTML FILE
    RewriteCond %{REQUEST_URI} /$
    RewriteCond %{REQUEST_URI} !^/(wp-admin|wp-content/cache)/.*
    RewriteCond %{REQUEST_METHOD} !=POST
    RewriteCond %{QUERY_STRING} =""
    RewriteCond %{HTTP_COOKIE} !(wp-postpass|wordpress_logged_in|comment_author)_
    RewriteCond %{DOCUMENT_ROOT}/path to/wp-content/cache/cachify/%{HTTP_HOST}%{REQUEST_URI}index.html -f
    RewriteRule ^(.*) /path to/wp-content/cache/cachify/%{HTTP_HOST}%{REQUEST_URI}index.html [L]
</IfModule>
# END CACHIFY

when I add this code into htaccess using bps/custom code or manual method the site goes 500 internal server error. How can I add this code while using BPS?
I also have custom speed boost cache code and some additional codes in my bps.