I am struggling with getting material variations with packed primitives when using a Copy SOP.

The example is a forest, e.g. a fairly complex tree with 100ks of leaves.

With the Instance object, it was possible to assign a shop_materialpath and material_override to points, e.g. to change BaseColor.

With packed primitives and the Copy SOP, adding a material_override causes mantra to completely ignore the assigned material. A way to get around this is to assign a material_stylesheet. Unfortunately, material_stylesheet causes mantra to unpack all the packed primitives which quickly exhausts all available memory.

Here is an example file: https://drive.google.com/file/d/0B3SRWSd2MwvPQndFcWhOTUlrcVE/view?usp=sharing [drive.google.com] (25M)

Any ideas would be appreciated.