Righteo, I have found the problem.

The show stopper is the "addThis Toolbar" which has been located in the "Sharing" row where, aside from being able to capture a link URL, email (using addThis or Gmail) or print the results, you can broadcast your itinerary to Facebook, Twitter, StumbleUpon and many other internet places quite happy to track your activity.

At my worksite, most addThis functionality as well as facebook are completely blocked. This includes any url links and internal java procedures/functions that even mention those words.

I also have addThis blocked on every computer I use. I also use ....... which till now had hidden the google ad server boxes - only noticed on the alternative network box.

This is what is causing my issues.

I took a copy of the source and edited it to disable the addthis call (and the 'ad choices' FWIW) within the Javascript 'setlinks' function.

Running the modified version locally worked fine.