iCloud offloading active files

I love it when im working on some videos in Premiere Pro and iCloud just decides that its currently the best time to offload these files.

Another thing iCloud likes is to upload a 5mb file for hours, exactly when i'm using Premiere Pro, which makes the whole machine sound like and F15 on a runway and makes the work in Premiere laggy.

Im pretty sure that iCloud is the reason because i can see the difference when its inactive while i perform the same tasks in Premiere Pro.

So opening the upload list and trying to disable the upload by click "X" is not working, because clicking the "X" doesn't do anything, obviously.

Disabling WIFI is not an option because i need internet for my work.

So the question is - why iCloud sucks... Sorry..

How do i disable iCloud sync so i am able to do some work?