I already tried that.  What I ended up doing was to forget trying to add the Uploader control programatically in C#.  Everything I tried caused undefined indentifiers in JavaScript.  I instead just add an iframe inside of the update panel and set up the control in a new *.aspx page as the "src" attribute.  That was the only way I could get it to work.

All of the Uploader demos appear to be on static pages.  Cutesoft needs to make a demo that adds the control progromatically to the page via the server in VB and C#.