Oh gosh, that is awful.
I guess another solution CB should offer would be to post an email address where kids could email in their responses, say within 10 minutes of the 5 minute upload period ending. The emails would be time and date stamped, so CB would be able to verify submission time.
Is there another computer in the house your daughter could use? Make sure she has Windows updated, etc. etc.?
My DD will flip out if this happens.