[CCleaner not working on MacOS Sierra 10.12]

If you have the Pro version, selecting browser Monitoring from the Options menu allows you to select browsers to monitor.  When I changed my settings to Secure Mode 7-passes, the monitoring feature did clean the browser when you close the browser  At least there was nothing in the Analysis window after it cleaned.  Whether or not it actually does a secure 7-pass wipe is undetermined.  Either way, there is some updating to be done to work correctly in Sierra.

[CCleaner not working on MacOS Sierra 10.12]

The problem occurs in Sierra when choosing any of the Security Options, so 1-pass or more does not work.  I was able to get it to work if I select Normal Mode (no security passes).