If this black box goes away when you change the composition zopm factor then you are probably looking at a graphics driver problem. A little system information would help us diagnose your problem.
It doesn't change when I change the composition zoom factor, unfortunately.
EDIT: My specs:
Processor Intel(R) Core(TM) i7-4770K CPU @ 3.50GHz Video Card NVIDIA GeForce GTX 780 Ti Memory 8.1 GB Operating System Microsoft Windows 7 Ultimate Edition Service Pack 1 (build 7601), 64-bit
Is your After Effects up to date?
Yes. I updated it just the other day.
Have you tried clearing the cache?
What happens if you try it in AE 12.2.1?
Wait, how the heck do you have 8.1 GB of RAM?