Will Goldstone turtorial; wall of cubes not normal, just exploding.

So I am following the Goldstone Unity 3D beginners guide (Game Development Essentials).
Following the basic instructions, it has had me create a cube on a floor, apply RigidBody to said cube and a color material, and snap duplicate the cube to make a wall.

Yet, when I launch the game (I have my camera in front of the wall so I can see), it just explodes and scatters the cubes everywhere. Since later in the tutorial I’m supposed to shoot it down, I think it’s supposed to be stood still when I launch the game (as a wall would), yet without any prior scripting it just explodes. What am I doing wrong?

This is nothing to do with Animation, there is no animation involved with this point in the book. If you have snapped these all correctly, there shouldn’t be any more than a slight jitter only noticeable when zoomed in - nothing should fly apart. If Colliders intersect during edit time, then you press Play, then you’ll see them being forced apart by the Physics engine.

I think you’ve probably just duplicated one of the blocks twice by mistake, and left one in the same place as another which would cause this problem, double check them all position wise.