[MeMeMe]

Edit- after working with this for a bit (twisting knobs and pushing buttons ) I realize that maybe the problem is me. I have been initiating the download with the "Get Artwork" button in the quick nav window. If I actually navigate to the addon and launch it the behavior is just what it should be. Downloading in the fore ground with a progress bar. Perhaps the quick nav button is actually launching a different addon? Looks like everything is working as it should though. Thanks to everyone for your help. Does the downloader get artwork for every movie in my library every time it is launched?

Artwork Downloader can be launched in several ways, if a skin creator has enabled them. You were launchign AD by one of the other methods, that does it in the background.
AD by default does look for artwork for every movie each time you launch it, but doesn't redownload art it already has. There is a way to get art just for the currnetly selected movie, but the skin needs to have support for it. Not all do.