I am getting a warning when trying to combine meshes that have been written to via ApplyAndDisposeWritableMeshData. I get a useless console warning each time I try to add a mesh to the CombineInstance array from the array of meshes I wrote data to via ApplyAndDisposeWritableMeshData. Not sure if this is a bug or if I did something I wasn't supposed to. Another clue, I tried copying the Mesh data out piece by piece and was able to get CombineMesh to work but as soon as I tried copying the MeshData out using SetVertexBufferParams and SetVertexBufferData it stopped working. Seems like for some reason I'm not able to use SetVertexBufferData with CombineInstance. This is a pain as I have to copy out each piece of data separately. Seems suspiciously like a bug. Maybe someone at Unity has clues on why this might be the case.