Interesting - OBS is what I use to record. And I do usually record in Windowed mode, just because it's easier. You can resize your OBS recording window by grabbing any of the corners of the red recording area box in OBS, and pulling them toward the center of the screen. That'll shrink the window, then you just have to drag the window back into place. With any game, it takes some effort to get it sized just right. You'll also end up with mouse contrails anywhere you move the mouse outside the borders of the recording window, so I usually bring it all in Adobe Premiere and layer in a black box over whatever areas need masking. Hope that helps, and I'm glad you're enjoying the game!