Plugin Not Working

I uploaded this plugin…
https://www.ads-software.com/extend/plugins/advanced-category-excluder/

I believe I did it right. It showed up on my dashboard as ACE. I click on it and it goes to this………

https://the3dsneaker.com/wp-admin/advanced-category-excluder/main.php

I gotta be missing something here right?

Is this a good category excluder, making me able to put certain things on my homepage and others in different categories?

Also, when it is activated, I can’t post anything. I try to write and it won’t work.