Got a few bugs quashed in my project this weekend. One I found was the game window would scroll outside the game world. This, in turn messed with rendering of units and buildings. Thankfully I fixed the scrolling bug and with it the rendering one too.
I faced that errors a few times and I usually fixed it by making the window a composite component of the world. What kind of rendering error, invalid coordinates?
The units and buildings would start rendering off position by however much the window was outside the world bounds. Once the window couldn't scroll outside those bounds this issue vanished.