My system isn't currently set up to link to another site. I have it set to look in a specific directory. While expanding the capability is an option, a file that I don't control might not fit the right resolution or filetype. If it does I could display it without a problem, but I would still need to be able to create a thumbnail of it.
The screenshot system uses two separate files instead of scaling down on the server every time one is loaded. If you have any suggestions for how to work around that and would still find the capability valuable let me know and I can give it some further thought.