Update: so i have been playing around with the external links and dropbox and have some additional data for you. I have setup another page inmylens.com/map-test-2/ with 2 embedded maps. The first link, the one that is working, is a link to a gpx file in the dropbox public folder, you can see the url just above the map. The second link is located in a dropbox folder which i have shared and also shared the file but I am not able to make it work, I did try changing the prefix from www to dl but no luck. You can copy and paste the link into a browser and download the gpx file. I am not sure why or if you are aware what might be causing this.
My second question: is it possible to add a download attribute to your download link so it does not open the file in another window but instead downloads the file? I did try adding ?dl=1 to the end of the url but no luck. You can see more about forcing dropbox downloads http://www.dropbox.com/help/201/en
Thanks
Brad