Is there a way to change the color of the default blue background to black? I'm not looking to place a sky cube/sphere, I just want to change the color.

In the beginning of your main:

sky_color.red = 1;
sky_color.green = 1;
sky_color.blue = 1;

I would set Camera.clip_far to the lowest value you can get away with since
you will not have a sky entity to clip the cameras render range.

Thank you!

You should use 0's for red and green, but 1 for blue - it's the absolute closest you can get to black without being black. Having it exactly black (all zeros) seems to cause strange things to happen when outside (try it once and see what happens - things can look very weird). If using 16-bit color instead of 32-bit color, then you'd set blue to 8 instead, again the absolute closest possible. I have all the numbers and I've run many tests to verify this.