Virtual Directory proxypass

I'm looking to be able to hit my dnsname/gallery and access my turnkey linux gallery virtual appliance

I've got this working with subsonic and passing to the right server, i'm having trouble with gallery3.

server {
listen 443;
server_name myexternaldns;

index index.html index.htm index.php;
fastcgi_param HTTPS on;
include /etc/nginx/include/php;

ssl on;
ssl_certificate /etc/nginx/ssl/server.crt;
ssl_certificate_key /etc/nginx/ssl/server.key;
ssl_prefer_server_ciphers on;
ssl_protocols SSLv3 TLSv1;
ssl_session_cache shared:SSL:10m;


location /subsonic {
proxy_pass http://192.168.5.93:4040/subsonic;
proxy_set_header Host $http_host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header X-Forwarded-Proto https;
proxy_redirect http:// https://;
}
location /gallery {
proxy_pass https://192.168.5.15;
proxy_set_header Host $http_host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header X-Forwarded-Proto https;
proxy_redirect http:// https://;


now, when the virtual appliance for gallery is installed it's already preconfigured. It is hosted right at https://<ipaddress>

When i try https://<myexternaldns>/gallery, it passes, but only partial (i've attached what i get) when i try to login it returns the url as https://<myexternaldns> without the /gallery. How should my line look for the gallery entry?

nginx -v results: 0.7.67 i'm using the turnkey linux nginx virtual appliance.

Thanks for any help