It's automatically a window at the top left of my screen. I'm not sure what you use to make it windowed as it doesn't seem to have graphic options. I tried windowing it through Borderless gaming and it was full screen at first, but stayed white and still never showed actual video until I alt-tab'd back to it, in which case it was back to the small window.
I use Nvidia. My desktop is 1080p @ 144 hz. You guys have to switch to 720p / 60 hz everytime you play?
Edit: Ok I see the window option in SpiceCFG, that fixed everything. However, the FPS counter says it's just over 70, that can't be good...
What if I want 144 hz and 1080p? Is that possible?