That's what I suspected. I've never been able to move the hotspot on a canvas away from the center. I'm not sure they even use hotspots...but don't quote me on that.
Either they don't use them or it's a bug. For now you can try spawning them at an offset: Self.X + (Self.Width / 2), Self.Y + (Self.Height / 2), would place the top left at the position of the center.