I think the main problem is that I was using battery saver mode in FK Manager so the CPU frequencies etc were reduced and now that isn't active so the battery usage is higher.
Open up the FK manager and go to the 'tips' section. From there you ca...
Does the multi window mode go away?
Nope, you still get the side-by-side multitasking which is the default in Android 7.
Thank you so much for making this ROM! It works perfectly on my T580, it's infinitely better than stock.