Working with Prism

I just got Prism and very excited to use it.
I’m finding it’s very taxing on my system almost unusable. My computer is a couple years old (i7 3.8GHz 64GB RAM and a RTX 2070) is that not powerful enough?
In Premiere Pro, rendering is almost 2 hours for a 20 sec clip !

Also I’m using it on 2:39: aspect ratio, can’t figure out how to adjust it in AE to fit my frame. Any tips?