Daniel DeEntremont

I managed to get this working with a later version of Houdini with the following changes:

The new scene invoke node still uses the path "/electra.char/Base.rig/control_data," but you must instead add a Extra Outputs item (+) and paste the path into Scene Output Path field (no key).

THEN, create an UnpackFolder node, and the extract pattern should be "/electra.char/Base_control_data" (this can also be selected using the arrow icon and Rig Tree panel)
This will expose the transform detail attribute needed in the attribute wrangle

Plug the UnpackFolder into the second input of the attribute wrangle and it works again.

You may also need to specify "electra" as trh Character in the SceneAddAnimation node.

Thank you SO MUCH Guillaume for this insight btw!

I've found, similar to Convex Decomposition, that you can get better quality results by scaling up the input curves/geo.
In my case, it was wrapping a bandage around a rodent's limbs and, without scaling 100x, the output geo was empty.

Marek_Netzel
So few month have past since my initial reply. There are few additional things to say.

In UE5 there seems to be not convex collision meshes limit, you can put 1000 So there is no need to monitor what convexde composition SOP is generating.

The other thing is that you can actually export from SOP context with rop_fbx. You simply add primitive string attribute "name" with correct names per LOD stream.

"LODGroup/LOD0"
"LODGroup/LOD1"
"LODGroup/LOD2"
"LODGroup/LOD3"

and

"UCX_LOD0_0"
"UCX_LOD0_1"
"UCX_LOD0_2"

for convex collision shapes where the number at the end corresponds to segment attribute from convex decomposition SOP.
You can put a primitive wrangle after it and put

@name = "UCX_LOD0_" + itoa(i@segment);

During save don't for to toggle "Build Hierarchy from Path Attribute" in the rop_fbx and change standard "path" to "name".
When importing in unreal toggle "Import Mesh LODs" in the importing dialog (Mesh section).

THANK you!