Object.angle is the object's visual angle. Set it to 180, and it's upside down on the screen.
Object.moveTo.movingAngle is the angle of direction in which the move to behavior is moving, this one is calculated automatically while it's moving. I.e. you tell an Object to move from x0,y0 to x0,y10 then the object would physically move straight down, move To.movingAngle would be 180.
Imagine a clock, which moves to the right, having its hour dial stuck at 12 o clock. If I want the clock hour dial to always face up while the clock is moving, I would ignore the moving angle for my objects actual angle. Object angle would be 0 and my move To.movingAngle would be 90.
Now imagine a bullet.
Shooting it straight down, that would be 180 moveTo.movingAngle. Now, if my bullet would ignore the moving angle, my bullet would likely face right and move down.
If I want it to look pretty, I would tell my bullet object.angle to take the angle of the moving direction to make it look esthetically correct.
Bullet.angle = Bullet.moveTo.movingAngle
There is an option in the moveTo behavior to set the angle for you.(tick box)