Have been using 15 since its been out, and working fine. Created a backup of C: drive to H:\SystemBackup\Backup_HDD0_20171116_1017 on 16 November 2017. All worked ok.
Windows wanted to do an upgrade on 12th December, and before I let it do that, I attempted to create a backup of C: drive, as usual. Got this display in the backup dialog. Note that the title says Overall Progress 100%. But in fact no folder was created, and no files. I had to shut down, and let Windows do its usual upgrade stuff.
Came back to Paragon on the 15th, and attempted to do another backup, but failed with exactly the same message.
Looked in the log file, but did not see any entries after the 15/12/207, which was when I tried the backup.