@nic
I have replied to your support ticket, where I have asked some additional questions so that I can help you get things working asap.
However, I thought I would add here a quick option for getting output to display in a quad setup.
Using the Blend Maker, use the settings as shown. Creating a basic 2x2 layout with zero blend/overlap.
The above requires that Display 3 is a 4k (3840 x 2160) display, and will expect the video coming to this output to be in this format all ready.
So in your case we likely need to chop and matte your content into the correct format (please reply to support ticket).