In radial gravity mode heat tends to rise towards the top always, meaning that if you use radial gravity mode in conjunction with the new set ambient heat, if you create a 'planet' at the center, any heat created at the center will not spread evenly but will move upwards into an oval. It would be nice if in radial velocity mode heat spread away from the center of the screen equally in all directions (I know that this would be too hard to implement in the other gravity mode).