Looking at your log file, you didn't set a part size for your backup and you didn't run the Configuration Wizard.
You are trying to upload about 60Mb worth of backup in one shot, most likely you get a timeout error during the process.
First of all, please run the Configuration Wizard (the blue button inside the Configuration page), then set the part size for your archive to 10Mb and try again.
You can find such option inside the Configuration page, under the Archiver section.
That should fix your issue.
Davide Tampellini
Developer and Support Staff
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