Since updating LR to 7.3.1 (Mac OS 10.11.6), I'm having several problems. When trying to use adjustment brush, I make a stroke, it sits there doing nothing, the rolling beachball appears & disappears a few times, & finally a small bit of the brush stroke appears — took about 70 seconds. I’ve restarted the app & the computer to no avail. I’ve gone back to 7.3 and now have the same problem with it. Help!