I'm running viewer 7.1.7.0 and it NEVER remembers which monitor the remote session was displayed on. I have the main panel on monitor #2 (to keep it out of the way), and when I connect to a host, the world map splash screen always opens on monitor #2, and then the remote session to the host opens on monitor #2. I then move it to monitor #1 which is where I want it. But the next time I start a session, it always starts on monitor #2.
That is not the only problem I've noticed with window placement. I'll attach a screen shot. If I use file transfer, the transfer window opens but is partially offscreen. In particular, the Close button, as you can see. Even though I move it to a better place so I can click the close button, it always opens partially off screen on subsequent uses.
Neither of these problems are a big deal, but are somewhat annoying.