Strange behaviour when tearing interactive cloth.

Well, I'm trying to simulate breakable cardboard with interactive clothes in unity 4.3.3. I setted the parameters this way:

Please notice that I setted the tear factor to a very low value. But when I impact the clothes with a box collider, I obtain this weird result. (By the way, the yellow cones are a different mesh and act as expected).

I attached a simple script to the pinata's body to see if is being teared or not.

 using UnityEngine;
 using System.Collections;
 
 public class PinataDummy : MonoBehaviour {
 
     // Use this for initialization
     void Start () {
     
     }
     
     // Update is called once per frame
     void Update () {
         if(transform.GetComponent<InteractiveCloth>().isTeared)
             Debug.Log("Cloth teared!");
     }
 }

And I can see the message "Cloth teared!" printed in the console.

EDIT: Changing values I've noticed that the parts teared from the object actually "separates" from the main mesh and fall to the ground, BUT they seem to be still attached, just stretching the texture. (Edited parameters and results are shown in the upper images).

EDIT 2: Seems like Interactive Cloth works fine with planes (even with the same parameters I showed above), so I suppose the problem is the round, full-of-cycles mesh I'm trying to use. I tried splitting the mesh in two in Blender (so I broke the main cycles) and preventing vertex asociated with too much polygons, but it stills looking weird and messy on collision. Anyone knows which are the requisites for a mesh to work fine with Interactive Cloth? Thanks!

EDIT 3: Ok, new theory: could the problem be the triangulation? Watching carefully the default plane mesh in unity, it's triangulated in an uniform way, while my .fbx mesh is triangulated in kinda chaotic way... I don't know, I'm running out of ideas.

EDIT 4: I did a hand-made triangulation in Blender3D, and the mesh now have triangles ordered exactly like the default plane in Unity3D. Still not working.

Is this a bug or I'm doing something wrong? Any help or hint is very appreciated. Thanks in advance!