I'm having the same issue. Software update from the softaculous web interface shows "Fetching Latest File......Could not SAVE latest file......Continuing" and the corresponding files downloaded in /var/softaculous/xxx have a size of zero. After multiple attemps at updating the software through Softaculous web interface, it would eventually work for all packages.
How do we fix this issue? How does softaculous create and update files in directories owned by root?