Let's see if we can force your client to do the resolution we want. The first thing we can try is setting it via command line; the downside is that the settings might not work because the game reads data from the preferences. But just for fun set your Launcher Arguments in the launcher to: and see if that works. If it does not work, then we will likely have to edit your preferences manually. The easiest way to do this is to download a plist editor such as this, open it and search for unity.Portalarium.Shroud of the Avatar.plist. Once that is open you can search for Resolution and you should see settings for Height and Width - change those to width of 1920 and height 1080.