Cant Upload Backup file to new UCM6510


I went to load a copy of one of my UCM6510. Before that i made backup config and download it to my pc using UCM6510 web gui, then transfered to a USB key. When I tried to upload Backup file to the new UCM6510 with the newly made backup file, but cannot upload it because UCM6510 gives error “cannot upload file size too large”.
UCM6510 backup file size is 12.88MB. and they say no more then 10, but I am loading ONLY the Config file and nothing else from the back up. Please advise how to restore from this backup, or how i can work around the size problems?

latest firmware [Release_UCM6510_1.0.19.27.]


Restore from the USB copy which you plug into the UCM.