Yes, you’re right — in fullscreen mode, the escape key doesn’t work, but it does work if you double-click the escape key. Thank you for your feedback! In the next version, we’ll definitely make an alternative for the browser version. For now, you can either double-click escape or use the settings in the main menu.
The colors you’re seeing are likely due to post-processing, but it wasn’t intentional. Even when painting the robots, I used a palette with colors similar to UV mapping. We only used base materials from the palette throughout. I think, since it’s a 3D game, there might be a lot of light reflections, making the colors appear different. 
Sorry about that!