Hi David,
You're welcome and I'm happy to help:)
I suggest you recursively permission all files and directories with apache.kaltura, 664 for files and 775 for directories.
# find /opt/kaltura/app/cache -exec chown apache.kaltura {} \;
# find /opt/kaltura/app/cache -type f -exec chmod 664 {} \;
# find /opt/kaltura/app/cache -type f -exec chmod 775 {} \;
Should do the trick. If you're running on Debian or Ubuntu, it should be www-data.kaltura.