CreateMaterialPropertyBlock.cs

using UnityEngine;
using NextGenSprites;
using UnityEditor;
using System.Collections;

public class CreateMaterialPropertyBlock : MonoBehaviour
{
    [MenuItem("Assets/Create/Material Property Block")]
	public static void GenerateMaterialPropertyBlock()
	{
		var inHierarchy = (Selection.activeObject != null && AssetDatabase.Contains(Selection.activeObject) == false);
		var _sRend = (inHierarchy) ? Selection.activeGameObject.GetComponent<SpriteRenderer>() : null;
		if (_sRend != null)
		{
			var mBlock = new MaterialPropertyBlock();
			_sRend.GetPropertyBlock(mBlock);
			mBlock.CopyToPropertyBlock(_sRend.sharedMaterial);

			var obj = ScriptableObject.CreateInstance<MaterialPropertieBlockContainer>();
			obj.Block = mBlock;

			Debug.Log(obj.Block.GetFloat(KeyFloat.CurvatureDepth.GetString()));

			var path = EditorUtility.SaveFilePanelInProject (
				"Create a new Material Propertie Block", 
				"Material Property Block.asset", 
				"asset", 
				"Copy Pre-Renderer Data and Material Data to this new Material Property Block");

			if (string.IsNullOrEmpty (path))
				return;
			AssetDatabase.CreateAsset(obj, path);
			Debug.Log(string.Format("New Material Property Block has been saved in: " + path));
			EditorUtility.FocusProjectWindow();
			Selection.activeObject = obj;
		}
		else
		{
			EditorUtility.DisplayDialog("Error", "No GameObject with SpriteRenderer selected", "Ok");
			return;
		}
	}
}