Nitro187 - the only difference I can see from those logs is when it's moving around the backupN files it gets "SHARING VIOLATION" for one of them. But then it goes ahead and carries on anyway, which is why I don't understand why it hangs, it appears to show it continued after that and it must be hanging somewhere else.
Does this only happen if you have your actual .capx file in your Dropbox (or Google Drive) folder? You don't need to do that to back it up, just set one of your backup folders to the Dropbox and as you work on your local .capx it will copy it to Dropbox from time to time anyway. I'm pretty sure that backup process only copies a single file in one go, so it should work with these file syncing apps.