Back to WA for answers...
My "php_value upload_max_filesize" was set to 2MB, which I thought was the problem. However, setting it to 8MB still did not work. I've been on tech support with Rackspace Cloud Sites (my host) and the two of us couldn't track down any reason for the scripts failure since there are no errors displayed in the browser or logged by the server. As far as PHP, MySQL and Apache are concerned, the script appears to be working fine.
Now I'm back here hoping WA can help me figure out why files larger than 1.6MB are not being saved to the upload directory or being written to the db.
Here's the URL: