Optimization of phpBB by Przemo 1.12.8

The subject of the order is the optimization of the script: PHPBB by Przemo 1.12.8 along with a package of modifications to optimize the script for SEO

Link:http://www.przemo.org/phpBB2/forum/viewtopic.php?t=81173

I want the forum script to be optimized with the latest version of PHP supported by the servers, no “bushes” ie that there was no problem with the encoding of Polish characters. Finding and flying security holes, due to the script is already old and deviates from current standards. In addition, I want all modifications to which I sent a link were also optimized for a new fresh version of the main script. The script should also be optimized for PageSpeed. In the attachment I put a package with the version of phpbb by przemo and modifications to be already uploaded. Please give me a specific amount of the order.