So my read of this is that each Xpress512 is a single-universe USB-to-DMX adapter. So if you have 2 of those connected, then that would only account for 2 universes - one per Xpress512?
I wasn't clear on my post. I updated it to read better.
To get 2x additional universes from the DMX-AN2, there needs to be 2x Xpress-512's connected via USB. With just 1x Xpress-512 connected via USB, the DMX-AN2 only outputs 1x additional universe.
Looks like with a Xpress-1024 2x universe box that the DMX-AN2 should output 2x universes. I have an Xpress-1024 ordered.