I also have a question regarding this. I do know what CORS is and how to deal with it on the server. But I want an app that is not hosted on a server it is just a local app via file://.
According to the polymer site under Using Elements the statement says
Note: You must run your app from a web server for the HTML Imports polyfill to work properly. This requirement goes away when the API is available natively.
Since Chrome latest supports the API natively then I would think we should be able to run apps without a webserver, but back to the CORS issue normally you fix it via server Header’s Access-Control-Allow-Origin “*”
How can you fix this if you are not using a web server?