The problem you're seeing is actually related to a bug we're trying to find a fix for.
To give you an idea of what's going on, the system is looking at that layer's initial location, instead of where it ends up. When you initiate the drag, it's assuming the layer's position is it's original position and pops the layer to that original XY position. That's why it's disappearing; it's being moved off screen instantly.
Hopefully we'll get a fix for this in place soon, but right now there's no workaround. The best way to achieve this would be to move one layer on the screen load, then instantly move it off screen while simultaneously moving the identical, draggable layer in it's place.
It's messy kind of swap, but it will get the experience you're looking for.
Please let me know if you have any questions about this or need more info.