I changed the progress bar's HTML around a little bit to make it easier to style. Instead of a table it now uses a layout like this:
<div class = "value of binding progressBarContainerClass" > <div class = "bar" style = "calculated width percentage"></div> </div>
There is also a new binding for "linkClass" that allows you to stylize the upload button
Here's a progress bar attached to a thread that is just incrementing the progress value.