Hi Bryan,
Obviously, once the upload is completed the user goes to a new page, so that's not such a big deal.
the message to display when they click the "save" button, warning them that it might take a bit of time to upload, is also do-able, but I'd need to add some code - so it'd only be in NT6. If you can't go to NT6 then I guess some custom javascript would be the right approach. (Let me know.)
cheers
Bruce