NGINX configs not working

I've added the following code to my nginx server but it's not applying to Hummbird interface (as in when I select re-check) it still shows disabled...I've tried creating nginx.conf and placing it in my directory, but since I'm using dreamhost I have to place the file within my /local/nginx directory.

Can you please point me in the right direction? I'll provide credentials where needed because I need to get this fixed as soon as possible.

location ~* \.(txt|xml|js)$ {
expires 8d;
}

location ~* \.(css)$ {
expires 8d;
}

location ~* \.(flv|ico|pdf|avi|mov|ppt|doc|mp3|wmv|wav|mp4|m4v|ogg|webm|aac)$ {
expires 8d;
}

location ~* \.(jpg|jpeg|png|gif|swf|webp)$ {
expires 8d;
}