Hi, I hope what I'm going to write will help you and you'll be able to offer me a pizza sometimes....;-)
I tried to read a lot of forums and to uninstall a lot of apps like Messenger.. Battery Doctor, QuickPic, etc. which come from Cheetah in Play Store.
I didn't have Lux, Twilight and other apps all you mentioned about the changing of brightness.
Infact I still have the issue but tonight while I ate a pizza (I'm pizza lover) I was playing with my phone to try and fix the issue and I didn't touch my phone because I had my hand with tomato and I noticed that you can get the accesses for all when you change the orientation and your phone is on the automatic orientation!!
However I hope the issue will be fixed as soon as possible. I got this issue after my upgrade at last MM on my phone.