Description of my issue: After upgrading to 4.5.1 Akeeba Backup had a warning that my secret word was not strong enough with a button to click to install a stronger one. I clicked the button, it implied the stronger secret word had been applied, but the next time I went into Akeeba Backup I received the same warning. Upon checking, the stronger secret word had NOT been installed. I clicked the button again, then inspected my secret word setting and confirmed it had NOT been installed.
Workaround: I manually copied and pasted the suggested stronger secret word - installing it myself manually. Problem solved for me via this workaround on all my sites. (But probably not for several of your other customers).
Semi related, after upgrading to Joomla 3.4.7 but before upgrading Backup to 4.5.1, my cron scheduled backups failed. I noticed Version 4.5.1 addresses this specific problem. I REALLY appreciate how fast you rushed out a fix for the problem. Thank you. My front-end (testing) backups worked with 4.5.1. I'll know tomorrow whether 4.5.1 fixed the problems with my cron bacups (after next scheduled run. Again, I appreciate your rapid response to the problem 4.5.1 fixes. Thank you!