Ever since upgrading to both CC 2015.6 1078672 and Mac OS 10.11.6 I've found that Lightroom takes over 2 minutes to log in and get past the splash screen to the real application. This was not happening before the upgrade. It was within 15 seconds prior to that. I do NOT have the problem with my Macbook Pro running 2015.7 LR and OS 10.10.5. It comes up right away, within seconds. I have over 300 GBs of open disk space on my 1TB drive.