http://forum.unity3d.com/threads/standard-shader-how-to-add-lightmap-from-3dsmax-on-uv2.278166/#post-1923095 Modifying the Standard shader is not a way to fix it. Lightmaps should go where they belong and that is the LightmapSettings.lightmaps array. A specific Renderer can then use a lightmap by using its index (Renderer.lightmapIndex) and then…

gistfile1.txt

using UnityEngine;
using System.Collections;

[ExecuteInEditMode]
public class SetLightmapsManually : MonoBehaviour
{
	public int m_lightmapIndex = 255;
	public float m_lightmapTilingX = 1f;
	public float m_lightmapTilingY = 1f;
	public float m_lightmapOffsetX = 0f;
	public float m_lightmapOffsetY = 0f;
	public bool m_setLightmapValues = false;
	public Texture2D[] m_lightmapArray;
	public bool m_setLightmapArray = false;

	void Update ()
	{
		if (m_setLightmapValues)
		{
			m_setLightmapValues = false;

			Renderer r;

			if (r = GetComponent<Renderer>())
			{
				r.lightmapIndex = m_lightmapIndex;
				r.lightmapScaleOffset = new Vector4(m_lightmapTilingX, m_lightmapTilingY, m_lightmapOffsetX, m_lightmapOffsetY);
			}
		}

		if (m_setLightmapArray)
		{
			m_setLightmapArray = false;

			if (m_lightmapArray.Length > 0)
			{
				LightmapData[] lightmapData = new LightmapData[m_lightmapArray.Length];

				for (int i=0; i<lightmapData.Length; i++)
				{
					lightmapData[i] = new LightmapData();
					lightmapData[i].lightmapFar = m_lightmapArray[i];
				}

				LightmapSettings.lightmaps = lightmapData;
			}
		}
	}
}