Backup and restore

Turn on all error messages then try another restore, see if you can pinpoint where it is stopping. Without getting too specific, it is possible there is a change in the database and it is not responding to something that is in the coding of the backup, causing it to wait. It is possible that the backup is waiting for a plugin to respond, but a change there is not reacting the way it should so the restore is not continuing. Sorry, not being deliberately vague, but what it may mean is that you rename the *.mbz file to a zip file. Extract everything and either edit the xml to get around any issue pinpointed, or rebuild the course using the materials from the extraction. I've done this in the past, and it works, but you have to get everything right. I've also had the time to do it, test it, fix it, test it, fix it again, test it, get it working, on my test site, so perhaps a better option may be just to rebuild the course.