Help Desk Ticket Reference: https://c.na7.visual.force.com/apex/Case_View?id=500A00000045ruY&sfdc.override=1
project_key: JBEPP

It seems that the Gadget proxy and cache configurations in eXoGadgetServer.war/WEB-INF/classes/containers/default/container.js don't take effect. 

Here is how this issue could be reproduced.

1) create a remote gadget that includes an image, for example: <img src='http://www.google.com/images/logo_sm.gif' >

2) modify the  eXoGadgetServer.war/WEB-INF/classes/containers/default/container.js
   change the default setting:
          "gadgets.content-rewrite" : {
                     "ga  "include-urls": ".*",
                      "exclude-urls": "",
                      "include-tags": ["link", "script", "embed", "img", "style"],
                      "expires": "86400",
                      "proxy-url": "/eXoGadgetServer/gadgets/proxy?url=",
                      "concat-url": "/eXoGadgetServer/gadgets/concat?"
             },
   to
             "gadgets.content-rewrite" : {
                     "ga  "include-urls": ".*",
                      "exclude-urls": "",
                      "include-tags": ["link", "script", "embed", "img", "style"],
                      "expires": "0",
                      "proxy-url": "",
                      "concat-url": "/eXoGadgetServer/gadgets/concat?"
             },

     The page source shows
              <img src='/eXoGadgetServer/gadgets/proxy?url=http%3A%2F%2Fwww.google.com/images/logo_sm.gif&gadget=http%3A%2F%2F16.157.132.22%3A8180%2FmyRemoteGadget.xml&fp=-182800334&refresh=86400
     no matter what changes made to the container.js file.

It seems that "proxy-url" and "expires" values are hard-coded.