Not at present, although it could be added as an option in an update. Right now though, since FTP Watcher is not an AppleScript but a fully fledged app, it's not possible to extend it.
You could try an AppleScript with a Folder Action in the Finder and script Yummy to upload then delete. Try it, and see how you get on - you can mail me (support at yummysoftware dot com) if you need any help.