Here’s a video walkthrough that shows how to get tangent data on the source actor and copy it to the actor copies. It’s basically a two-step process: first, copy the tangent data to a custom attribute on the mesh proxy, and the copy the attribute from the proxy to the actor copies. That’s basically what CrowdFX does for you for the default Texture_Projection.

I did this video for a customer who wanted the tangent data for the normal maps on the actor copies.