Помогите разобраться с .htaccess

#####################################
# ShopCMS: Скрипт интернет-магазина
# Copyright (c) by ADGroup
# http://shopcms.ru
#####################################

Options +FollowSymlinks -Indexes -MultiViews
DirectoryIndex index.php
ErrorDocument 404 /404.html

php_value session.use_trans_sid 0
php_value session.use_cookies 1
php_value session.use_only_cookies 1
php_value session.auto_start 0
php_value magic_quotes_gpc 0
php_value register_globals 0
php_value display_errors 0
php_value magic_quotes_runtime 0
php_value allow_url_fopen 1

RewriteEngine On
Redirect 301 /product_254.html http://www.site.ru/product_3.html
RewriteBase /
RewriteCond %{THE_REQUEST} /(\.+) [OR]
RewriteCond %{THE_REQUEST} /(\?+) [OR]
RewriteCond %{THE_REQUEST} /(/+)
RewriteRule ^(.*)$ 404.html [L]
RewriteRule ^core/(install|temp|smarty|modules|languages|includes|functions|fonts|files|config|classes|cache|backup)/(.*) - [F]
RewriteRule ^data/(.+)\.(tpl\.html|php|php3|php4|php5|phtml|pl|cgi) - [F]
RewriteRule ^install_check\.html$ install.php?check=yes [L]
RewriteRule ^index\.html$ index.php [L]
RewriteRule ^news\.html$ index.php?news=yes [L]
RewriteRule ^price\.html$ index.php?show_price=yes [L]
RewriteRule ^cart\.html$ index.php?shopping_cart=yes [L]
RewriteRule ^wide_search\.html$ index.php?search_with_change_category_ability=yes [L]
RewriteRule ^feedback\.html$ index.php?feedback=yes [L]
RewriteRule ^compare\.html$ index.php?comparison_products=yes [L]
RewriteRule ^page_([0-9]+)\.html$ index.php?show_aux_page=$1 [L]
RewriteRule ^product_([0-9]+)\.html$ index.php?productID=$1 [L]
RewriteRule ^category_([0-9]+)\.html$ index.php?categoryID=$1 [L]
RewriteRule ^category_([0-9]+)_offset_([0-9]+)\.html$ index.php?categoryID=$1&offset=$2 [L]
RewriteRule ^category_([0-9]+)_show_all\.html$ index.php?categoryID=$1&show_all=yes [L]
RewriteRule ^show_news_([0-9]+)\.html$ index.php?fullnews=$1 [L]

<IfModule mod_nginx.c>
# Блок правил для сервера Nginx.
# В случае его использования необходимо вставить нижеуказанные правила в файл nginx.conf в секцию location/ для вашего сайта.

location ~* /core/(install|temp|smarty|modules|languages|includes|functions|fonts|files|config|classes|cache|backup)/(.*) {
return 403;
}

location ~* /data/(.+)\.(tpl\.html|php|php3|php4|php5|phtml|pl|cgi) {
return 403;
}
rewrite ^/install_check\.html$ /install.php?check=yes last;
rewrite ^/index\.html$ /index.php last;
rewrite ^/news\.html$ /index.php?news=yes last;
rewrite ^/price\.html$ /index.php?show_price=yes last;
rewrite ^/cart\.html$ /index.php?shopping_cart=yes last;
rewrite ^/wide_search\.html$ /index.php?search_with_change_category_ability=yes last;
rewrite ^/feedback\.html$ /index.php?feedback=yes last;
rewrite ^/compare\.html$ /index.php?comparison_products=yes last;
rewrite ^/page_([0-9]+)\.html$ /index.php?show_aux_page=$1 last;
rewrite ^/product_([0-9]+)\.html$ /index.php?productID=$1 last;
rewrite ^/category_([0-9]+)\.html$ /index.php?categoryID=$1 last;
rewrite ^/category_([0-9]+)_offset_([0-9]+)\.html$ /index.php?categoryID=$1&offset=$2 last;
rewrite ^/category_([0-9]+)_show_all\.html$ /index.php?categoryID=$1&show_all=yes last;
rewrite ^/show_news_([0-9]+)\.html$ /index.php?fullnews=$1 last;
</IfModule>