Is one vertex assigned one particle?

[arowanaito]

At runtime, skinning is performed by Unity's skinned mesh renderer component. Obi is not involved in skinning at all, it just provides the initial weights.

As you can see in any of the included sample scenes, vertices move with different weights. Otherwise deformation would look extremely rigid. See for instance the RubberDragon sample scene: there's +30000 vertices in the mesh, but just a few hundred particles.

Make sure the maximum skin radius is large enough so that each particle can influence multiple vertices, and that the amount of weights in the skinner is 4.

let me know if you need further help,

I think I've solved one of my problems.

One case where I was able to get multiple particles to act on a single vertex was when I added a MeshFilter and MeshRenderer to a GameObject, and then added an ObiSoftbodySkinner. This will automatically generate a SkinnedMeshRenderer.
On the other hand, when a single particle was applied to a single vertex, the SkinnedMeshRenderer was already attached to the GameObject, and the ObiSoftbodySkinner was attached to it.

In my failed example, when I set the SkinningMaxDistance to a very large value, all vertices seemed to move according to the same single particle.

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