I've been trying to understand how instancing with attributes is working, been following this tutorial: https://www.youtube.com/watch?v=Hw-XcMe7B3E [www.youtube.com]
I added the string from the attribcreate to the HDA, added heuassetpath to the Tags of the parameter.
When I place a prefab in Unity in the slot it generates a bunch of extra objects that are not in the HDA, but in the scene

Turns out it was just a bug in Houdini 19.0.383, made the update to 589 and it works perfectly

thats good to know thanks. I'm seeing the same thing in 561