On motor, I guess the V going into the tail will ease out the wall. But I'm not sure.
So if it fails to start please try with the config in that 3D model also.
Why I'm saying this ?
Because if you see this video
there is obviously a wall where the head and tail meets and that guy must move the magnet out to get it going.
But if you see this one
there is no wall at the junction, may be because he made it overlap, just like this german dude.
But I can't see it clearly, so I'm not sure.