Custom TerrainGridTileLoader

Hi Guys
Ive been bashing my head against this problem for about a day now with no success… So i thought i would post it her to see if any one had any ideas…
I started with TerrainGridTest which worked great…
But i wanted a more earth like terrain so i downloaded a heightmap guillotined it into 16 pieces. and used that. And that worked great too!!

But now wanted two more things.

  1. the terrain was just too rough. looked a bit like minecraft.
  2. i wanted a pre-created NavMesh for my charaters

so using the SDK scene composer I created 16 empty jme3 scenes. Added a terrain to each scene based on each of the height maps. and applied a consistent level of smoothening, and generated a NavMesh for each.

then i created

class CustomTileLoader implements TerrainGridTileLoader {

    public TerrainQuad getTerrainQuadAt(Vector3f location) {
        final int roundX = Math.round(location.x);
        final int roundZ = Math.round(location.z);
        String modelName = assetPath + "/" + name + "-" + roundX + "-" + roundZ + ".j3o";
        Logger.getLogger(this.getClass().getName()).log(Level.FINE, "Load terrain grid tile: {0}", modelName);
        TerrainQuad quad = null;
        try {
            Node model = (Node) manager.loadModel(modelName);
            quad = (TerrainQuad)model.getChild("terrain-world_grid-" + roundX + "-" + roundZ);
            quad.setMaterial(null);
        } catch (Exception e) {
            //e.printStackTrace();
        }
        if (quad == null) {
            Logger.getLogger(this.getClass().getName()).log(Level.WARNING, "Could not load terrain grid tile: {0}", modelName);
            quad = createNewQuad(location);
        } else {
            Logger.getLogger(this.getClass().getName()).log(Level.FINE, "Loaded terrain grid tile: {0}", modelName);
        }
        return quad;
    }

Which is basically a copy of AssetTileLoader customized to load terrains from the jme3 scenes i created. But Alas i can not get it to work… It seems to find the terrains but Im just seeing the skybox instead of any terrain. Soo…
Is this a good idea ? is this a good approach to get a smoothened realistic explorable terrain?
Any ideas as to where i might have screwed up?
So my files are indexed 0-3 so world_grid-0-1.j3o is that ok or does it need start with negative numbers… It didnt seem to matter when i was working with just heightmaps