By the way, what is the sprite hotspot ?
A Sprite's hotspot is its origin.
So when you use Sprite.X or Sprite.Y, C2 has to decide which of all the pixels on the Sprite represent its coordinates.
That's what the hotspot/origin does.
For Sprites, you can choose a hotspot everywhere on the Sprite (in the image editor).
But for dynamic graphics, like Tiled Backgrounds, your selection is restricted and you can only choose from 9 fixed points (in the object properties).