I'm using another script that I've put into the "classes" directory. It has its own htaccess instructions for inclusion, with virtually all of the rules as rewrites in the "classes" directory.
Wordpress MU has the following htaccess requirements:
RewriteCond %{REQUEST_FILENAME} -f [OR]
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule . - [L]
RewriteRule ^([_0-9a-zA-Z-]+/)?(wp-.*) $2 [L]
RewriteRule ^([_0-9a-zA-Z-]+/)?(.*\.php)$ $2 [L]
RewriteRule . index.php [L]
THIS IS THE OTHER SCRIPT
RewriteRule ^classes/category/(.+)$ /classes/index.php?cat_name=$1 [NC,L]
RewriteRule ^classes/class/(.+)$ /classes/index.php?post_permalink=1&post_id=$1 [NC,L]
RewriteRule ^classes/profile/(.+)$ /classes/index.php?show_emp=$1 [NC,L]
RewriteCond %{QUERY_STRING} .+
RewriteRule ^classes/page([0-9]+) /classes/index.php?%{QUERY_STRING}&class_page_link=$1 [NC,L]
RewriteRule ^classes/page([0-9]+) /classes/index.php?class_page_link=$1 [NC,L]
</IfModule>
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The LAST WP one, the . index.php [L} line is causing "file not found" errors in the classes directory script. If I remove that instruction, the other script works but the entire worldpress MU goes down. Any ideas on how to solve something like this? Probably happens often with other scripts?