I see lightmaps ate not supported. But unity will gpu batch as long as the gpu instanced lrefabs share the same lightmap file. Couldnt that be the case here? With Bakery Ive control over what objets are mapled into same lightmap and the I do have the prefabs I whant to gpu instantiate in resources folder and they instantiate and get originals prefab lightmaping. Gpu instancing breaks for some but at least it somewhat works unlike without the script. I wonder if your asset would do a better job.